Saturday, November 21, 2009
Sunday, November 15, 2009
Now is the time to actually print our great piece of work!
• Choose Print command from File menu.
• Choose your printer from this list. In most of the cases default printer would be the right one.
• Click here to choose All. This would print all the pages of the present document.
• Click OK button to Print.
Print Preview
Once you have completed spelling for the entire document, now is the time to sit back and take stock of your work. Because of advanced WYSIWYG feature (What You See Is What You Get) in-built in MS Office, you can see a preview, on screen of what you wish to print. In most cases, this preview would give you an exact replica of what your printer would print. This is very helpful, since you save considerable amount of time and money (in printing and stationary cost) by making sure that your document looks exactly the way it should, before you finally print it.
• Choose Print Preview command from File menu
A This is what appears on the screen. An exact copy of the page, which your printer would print. If you are happy with what you see, go ahead and print the document. If not, go back to the main screen by clicking on Close button and make necessary changes.
Spelling
Once the entire matter has been typed and formatted as required, now is the time to make sure that no spelling mistakes have been made. Spelling is one of the coolest features of Word and frees you from the bother of concentrating on the spelling of your text.
• Place the cursor right in the beginning of the document to ensure that the complete document is spell checked. (Although even if you place the cursor anywhere in the middle, Spelling features will prompt you and start from the beginning)
• Choose Spelling and Grammar command from the Tools menu.
• A Spell Check dialogue box appears. The spell check program immediately starts picking up each word in your document and searching that word in its dictionary. If the word is found in the dictionary, the program moves on to the new word till it finds a word, which does not exist, in its in-built dictionary. At this stage this dialogue box will prompt you with the word, which is not in Dictionary, and ask you what you wish to do now. The program would close when spelling has been completed on the entire document.
Explanations for some of the options in the spell-check program are given below:
Indenting
Now to further dramatize the effect of this bullet, we can indent the text still further so that the Terms and Conditions stand out from the rest of the text.
• Highlight the text and choose Paragraph command from Format menu.
• Type "1" for left indentation. You may see in the preview that the highlighted text has moved further to the right.
• Click once on OK button.
A Notice the entire block of text has been shifted (indented) by one inch towards the right.
Bullets
Just as we can create numbered lists, we can also create Bulleted lists. The main difference here is that instead of consecutive numbers in case of numbered list, items appear with the same chosen bullet mark.
• Highlight the text and choose Bullets and Numbering command from Format menu.
• Click on the Bulleted folio/ tab.
• Choose the bullet mark you wish to apply by clicking once on it.
• Click on the OK button on continue.
A Individual lines appear with bullet mark with hanging indent effect.
Numbering
One of the really smart features of Word is to create numbered lists. Old Word processor users would appreciate, how much time was wasted in tying to manually create a perfectly aligned numbered list. Through this feature, once you have chosen a list of items separated by Enter key, you can ask Word to automatically assign consecutive numbers to this list.
• Highlight the text.
• Choose Bullets and Numbering command from Format menu or click once on the numbering icon.
• Click here to choose Numbered.
• Choose the numbering pattern you with to apply b clicking anywhere inside the chosen pattern box.
• Click once on OK button.
• Items are automatically numbered with hanging indent effect.
Justifying Text
Having learnt to align text, we shall now apply this knowledge to justify a whole paragraph between the left and right margin ('Blocked' lines in the figure).
• Highlight thee entire paragraph.
• Choose Paragraph command from Format menu.
• Choose Justified option from Alignment pull down list.
• Click once on OK button.
A You can see that the text has been perfectly adjusted (justified) between the left and right page margin of the page.
Underling Text
Now having centered the text, we wish to underline it.
• Highlight the text. Choose Font command from Format menu.
• Choose Single Line option form the 'Underline' pull down list.
• Click on OK button to continue.
Align Text
Now let us learn to change the alignment of text. By default, text is always left aligned.
• Highlight the line by dragging the mouse till the end of text.
• Choose Paragraph from Format menu.
• Choose Indents & Spacing folio by clicking on it once.
• Choose the option Centered from 'Alignment'.
• Click once on OK button.
In Word you can indent any length of selected text. You can indent from left margin, from right margin or form both margins.
B There are three options for special Indent--None, First line and Hanging. Choose all these options one by one and after seeing its preview in the preview window remove and select the one you like.
Changing font size
• Highlight the text as explained earlier. Click here to see a list point size. These numbers refer to the size of the characters that you wish to format. Higher the point size number, bigger would be the character size of the highlighted text. (Choose 10 here, for the given example). Please remember that before you choose that point size, the range of text (for which you wish to increase or decrease point size) much be selected (highlighted) first.
A You can see the text has changed according to the font and point size chosen by you.
Alternative Method
There is an alternative method of change the font. Highlight the text as explained earlier by 'blocking'. Choose Font from the Format menu. A window will appear.
This is a very compact and feature rich dialog box. Through this you can change not only the fonts and point size, but also the styles like Bold, Italics, Bold Italics, and Regular etc.
You can also apply other effects like strike through, underline etc. Choose the desired font, font style and size and click OK button to continue.
• Choose Font command from Format menu.
• In case you wish to underline the selected text, choose form the alternatives given her--None, Single, Words only, Double and Dotted.
• Click OK to continue.
Changing font
• Place the mouse pointer at the beginning of the text. Click the left button and start highlight the entire text by dragging the mouse till the end of the text. Of course, you may alternately begin from the end & move backwards toward the beginning of the text.
• Click at the font box of formatting toolbar. Click once at the pull down arrow symbol and a list of all the available fonts would be displayed. Use the mouse to move up and down in this list. Click at the font that you wish to appl. 'Arial' font has to be chosen for our present exercise. The moment you have clicked and chosen a particular font, this pull down list would automatically close and the selected font would be applied to the highlighted text.
Entering text in text box
A After you have finished typing, your letter should look like this. If you made some mistakes while typing, refer to navigation instructions about how to make modifications, deletion and additions to existing text.
• Click here and type the slogan 'Creativity & Synergy'.
Entering Text
• Click here and type out the sender's (Your) address and phone numbers.
• Click here with the mouse and type the name of the company.
A Note that the current date is automatically displayed here. In case a wrong date is show here, go back to Windows and change the current date and time setting.
• Click here and type the name of the recipient and his company address (as per sample exercise given before).
• Click here and type the title and recipient's name
• Place the cursor at the beginning of this Paragraph, click on the mouse, highlight this entire paragraph and Pres DEL key from keyboard. This matter would get deleted and now you can begin typing the rest of the letter as shown in the sample letter.
starting word
Choose MS Word command form Microsoft Office option of the Program option from Start menu.
New Document
• Choose New command from the File Menu. You can activate the menu in 2 ways.
1. Pres Alt-F key (or key underline in Menu line to activate that menu list) and use the keyboard to move up & down within the various options under the file menu option and press Enter to select an option.
2. Use a mouse. Take the mouse pointer to File and click. Automatically this menu list would be displayed. Use mouse to travel between various option and click once at the desire option.
• Click on Letters and Faxes folio to select preformatted templates for creating letters and faxes.
• Click here to choose Contemporary Lettery.
• Click once on OK button.
You will see a layout design of your document. Here, all you are expected to do is fill up the blanks and your document is ready.
Starting MS Word
Enough of theory! Now let us start working on our first document in Word. On the previous page you see Word Exercise I. We shall now learn how to create a document that looks exactly like this exercise.
Click once the on the Start button, highlight Programs, highlight Microsoft Office and then click once on Microsoft Word option. Or simply click once on the Word icon form the MS the MS Office toolbar, which is normally displayed at the top right hand corner of your screen.
You will see MS Word sign on banner briefly and then Word’s main screen would be displayed. This screen has already been explained on page no 4. The white blank area that you see is the page where you would be typing your matter. Notice the toothpick cursor at the beginning of first line, when you start typing, your matter would appear from this point on wards.
So let’s begin. Start typing the text given in Exercise 1. Type only till “Wide Area Networks, and much more” as shown below:
While typing do not bother how your text looks, simply go ahead and type in continuity. One of the basic features of Word is word wrap. This feature allows you to type in continuity without bothering about your line running out of right margin of your page. When you type as soon as you approach the end of a line (right side of your paper), Word automatically figures out whether the last word that you have typed, can fit within the current line. If it will, fine, otherwise Word automatically picks up the whole word and places it in the next line. When you reach the end of a paragraph or a paragraph heading (like – what is Internet after all?) press Enter to place your cursor in the next line. If you need a blank line then press Enter once more to create some blank space between two paragraphs.
This point is so important that I am going to repeat it once again. Never press Enter after every line, but only at the end of a paragraph or a paragraph heading. You can also split a single paragraph into two by placing the cursor at the end of the sentence after which you want to create a new paragraph and pressing Enter. For instance, if you want to split this paragraph itself into two and want to start the second paragraph with the sentence “You can also split a …”, place the cursor after the full stop of previous sentence “…or a paragraph heading.” And press Enter. Press Enter once again to create a blank line. You will see the results as.
While typing if you make any mistakes use the Backspace and Del key to delete the incorrect text. Backspace key deletes a character to the left of the current cursor position whereas Del key deletes character to the right of the current cursor position. As has been explained in previous pages, use the Insert key to alternate between Insert Mode and Overwrite Mode, as and when required.
After you have typed till the text shown above, if you see the remaining text in Word Exercise 1, you will notice that the subsequent text is a repetition of the same points about Internet, which have been briefly explained in the next section. This brings us to an interesting and very useful group of commands—Cut, Copy and Paste. Through Cut command you can move a block of text from once place to another. Through Copy command you can copy a block of text from one place to another such that the text appears at both the places. Paste command is used to insert the block of text, which has been either Cur or Copied. In the present example we will use the Copy and Paste command to copy the Internet features. Highlight all the Internet points by placing the cursor before “E-Mail”, clicking on the mouse’s left button, keeping it pressed and rolling the mouse till the end of “Wide Are Networks, and much more.” Release the mouse button now. This highlighted text, called a block can be either cut or copied. At the moment, since we want to copy, click once on Copy icon. Press Enter twice to come to a new paragraph and click once on Paste icon to get the same block of text here.
Now that you have a second block text, you can place the cursor after each point and type a brief explanation about it. Take care not to press Enter after the end of each point, otherwise a blank line would be inserted between points.
Now finally the typing work is over and we can begin work on improving the look of this document and making it look exactly like the sample exercise page. This process involving changing the font type, font size, alignment of text, applying shades and colors etc. is called formatting. So let us now start from the top of the document and move our way down.
Place the mouse pointer before 'W' of 'Word Exercise 1', click once, keep the mouse button pressed and roll the mouse to highlight this block of text, release the mouse button after reaching the end of the text (after '1'). You will see that the text (called block) is highlighted in black and the text appears in white color.
Now we have to make this text bigger, thicker and aligned to the right side. This would be done by three commands
• Increasing the font size,
• Applying Bold font style, and
• Right Aligning, respectively.
Click here once to see a pull down list of font sizes available. The bigger the font size, the bigger would be the text.
Click once on the Bold icon to apply bold style on the selected text.
Click once on the Right Align icon to align the text with the right margin of the text.
Now let us use the same technique to:
• Change the font,
• Increase the font size,
• Italicize the selected text,
• Underline the selected text, and
• Center the Heading horizontally between the pages.
Fonts are like different handwriting scripts available to you. Just as different people write the same alphabets differently, similarly using the font facility of MS Word, you can choose the way in which your alphabet script is displayed and printed. You can have the same font for the entire document or you could apply different fonts for different pieces of text to make your document appear more interesting and appealing.
Highlight the document heading "Internet - The world at the touch of a button!" using the technique explained earlier to mark a block.
Click here once to get a pull down list of all the fonts available to you. Choose the Impact font by clicking on it.
A Notice that each font is displayed in its own unique font style, so before you apply the font you can get to see what it looks like.
Click here once to increase the font size to 20.
Now since we want to Italicize only "The world at the touch of a button!" and not the entire heading, highlighted only this portion, leaving out the word "Internet", and click once on the Italics icon.
Now highlighted the entire heading once again and click on the Underline icon to apply underline style.
The next thing to be done on this heading is that it has to be centered between the left and right margins. The block is already highlighted, just click once on the Centre Align icon.
Now finally let us see how we can change the colour of this text. For this click once on the Font Colour icon and select the desired color - in our case Grey 50% by clicking on it.
Now let us move ahead. You would have noticed that typically the first line of a paragraph is slightly indented i.e. it begins not from the extreme left but slightly ahead. For doing this, place the cursor at the beginning of the first paragraph and press Tab key. You will see that the first line has got indented. Take care not to use the Space Bar to create this space, since this is not only more tedious and time consuming but may also result in different paragraphs having different indent spaces.
Let us now highlighted the paragraph heading "What is Internet after all?". Click here once, use the scroll bar to scroll down to the font "Helvetica", click on it to apply it to the selected block.
Click here once to get the font size pull down list and select point 14 by clicking on it once. Notice, the text would become bigger.
To give a highlight effect to any block of text, highlighted the text and click here once and select the desired highlight by clicking it.
Now move to the next paragraph heading "What can Internet do?" and use the same techniques just learnt to increase the font size, change the font and apply the highlight effect on this text as well.
Now let us learn how to create "bulleted lists". Frequently you have a number of points about a specific topic that you want to present separately. For this you can use bullets. No, not the ones that you put in a revolver but typographical bullets. These bullets are small marks at the beginning of each new point.
For applying bullets to points that already exist, highlight all the points (like in our case, starting from "E-Mail" and ending with "Wide Area Networks, and much more") and click once on the Bullets icon.
Alternatively you can also have bullet marks appear automatically when you begin a new point. For this places the cursor in a new blank line and click once on the bulleted list. Now type your first point, the moment you finish a point and press Enter the cursor will go to the next line a which will automatically have a bullet mark. When you have finished typing your last point, press Enter to go to a next line and click once again on the Bullets icon to turn the bullet list off. Bullet icon like most other icons on the Formatting Tool bar is a "toggle switch", which means that if you click on it once, it becomes On and if you click again on it becomes Off.
Similar to the bulleted list is the numbered list. In case of a numbered list each point starts with a point number (1,2,3... or A,B,C.. I,II,III... etc.) instead of a bullet mark. The procedure for this is similar to that of bullet list. Highlight all the points and click once on the Numbered List icon.
As we can see here that Word is taking the next matter as a part of the above matter, therefore it is showing the numbered list as sub-points of the above bulleted list. To correct this you indent these points to the left, click once on the Left Indent icon you will notice that all the points have moved to the left by one tab position. In case you want to further Indent click on the Left Indent icon again. If not satisfied with the results you can always use the Right Indent icon to bring back the text by one tab position at a time.
Notice all the points have a running number against them and the matter starts from a neatly aligned straight line. Try doing this manually by typing the numbers and using spacebar to create perfectly aligned text and it might take you more than fifteen minutes to achieve this perfectly, whereas through Numbered List icon it is a matter of seconds. Remember computers are all about saving time!
Now take a look at the Exercise 1 format given and apply Bold and Italics formatting on all the points
Congratulation! With this step you have completed your first exercise in MS Word. It may have taken you a bit of time to do it the first time but with practice you would become much more faster, efficient and hopefully more innovative.
Keyboard Operation
Typing keys The part of the keyboard which is used to type letters, numbers and other characters. The alphabets layout resembles a standard typewriter keyboard exactly, however there some extra keys for entering commands, e.g. Ctrl key, Alt key, Shift key, Enter key etc. On most keyboards these extra keys are grey in colour whereas the alphabet, number, symbol and punctuation keys are white in colour. The Ctrl, Alt and Shift key is always used in conjunction with some other key.
Shift and Caps Lock key The shift key is used to type capital letters i.e. if you want to type the letter “F”, you have to press the Shift key, keep it pressed with one finger and press “f” key with the other. However, if you want to type an entire word or a sentence in capital letters, use the Caps Lock key instead. Unlike the Shift key, Caps Lock key is a toggle key and does not need to be pressed continuously. Press it once and it becomes On (you will see the Caps Lock indicator on the keyboard lighting up when you do this) and thereafter whatever you type would be in capital letters, pres it again and it becomes off.
Function keys The row of 10-12 keys—F1 to F12 above the typing keys are called the Function keys and are used to execute special commands or as shortcut keys. The use of these keys varies from program to program, however within MS Office some degree of standardization has been achieved. In Word, the functions keys are used alone or together with the Shift, Alt and Ctrl keys to give commands.
Cursor control keys A group of special keys used to control and navigate the cursor arrow keys (Up, Down, Left, Right). Home and End are used to quickly place the cursor in the beginning or end of a line. To delete an alphabet to the left of the cursor press the Backspace key (normally above the Enter key), to delete and alphabet to the right of the cursor press the Del key.
Numeric keypad The keys on the extreme right of the keyboard (resembling a calculator’s keyboard), which can be used both – to enter numbers (when the Num Lock On) or to move the cursor (when the Num Lock is Off). The Num Lock key is located above the number 7 (Home) key on the Numeric keypad and its On or Off status is displayed by the Num Lock indicator light on your keyboard. Since Num Lock is also a toggle key, pressing it once makes is On and pressing it again makes it Off.
Note: Press the keys briefly with a light pressure, you want repeated characters.
Mouse Operations
Pointing Move the mouse pointer until the pointer is on the desired item.
Clicking Move the mouse pointer to the position you want, then press the mouse left button once.
Double-clicking Move the mouse pointer to the position you want, then press the mouse left button twice in rapid succession. Alternatively, if your mouse has been so installed, you can also click the middle button once, instead of pressing the left button twice.
Right-clicking In some cases like changing the properties of an object, or for correcting a mis-spelt word, or even for cut, copy and paste—the mouse right button can be used. In such cases, simply select the object and click once on the mouse right button.
Dragging Move the mouse pointer to the right place, highlight the desired text by clicking once in the beginning and releasing the left button at the end, then click once again in the highlighted block, keep the mouse left button pressed and roll the mouse to move the block to a new location by releasing the left button at the desired location.
At first, using the mouse may be difficult (particularly double-clicking and dragging). However, learning to use it is worth the trouble because many of the advanced tools in modern programs are only operated with the mouse. In any case most operations are much more simpler and faster to execute through the mouse rather than through the keyboard.
Part of Word Window
Please see Figure 8.1 for a visual image of all these parts. An active window has:
Title Bar: This tells you which application package is currently running and which document is currently open.
Menu Bar: This is the traditional Windows style drop-down menu. When you point to any menu title and click once with the mouse, the menu will open, displaying all commands available under this menu title. Clicking on the desired command would tell Word to execute that command. Some commands have ellipses (…) in front of them. These commands have further sub commands. Commands appearing dimmed cannot be executed unless the prerequisite functions required by that command have been performed, e.g. you cannot use the Copy or Cut command from the Edit menu unless you have selected a piece of text first. Many commands also have a keyboard shortcut specified against their names.
Standard Toolbar: Toolbars contain buttons, drop-down menus and other controls that help you quickly alter that appearance and arrangement of documents by executing a variety of Word commands. Toolbars are very helpful and convenient in quickly executing commands without having to go through menus. The standard toolbar contains icons for basic functions like opening files, saving files, printing files, cut, copy, paste etc.
Formatting Toolbar: This contains icons for changing the look of your text (called “formatting” in computer jargon); for example, there are icons for changing fonts, styles, font sizes, text alignment etc.
Ruler: The Ruler lets you make changes to margins and indents, and helps you create document as per dimensions required.
Scroll Tools: These help you travel within your document. You can go anywhere, up and down, right and left in your document mainly by two way: Using the horizontal and vertical scroll bars with the help of the mouse; or Using the keyboard to press PgUp, PgDn, Home, End and arrow keys.
Status Bar: Also called the Status Area, this is the normally the last line on your screen. This gives the following information about your work—
• Current Page
• Section Number
• Current/Total pages in the document
• Current Cursor Position (where the cursor is presently located)
• Current Column Number
• Record Macro—whether macro recording is On or not
• Track Revision—whether revisions have been made or not
• Extend Selection
• Over type Mode—whether you are in Insert mode or overwrite mode
• Help for WordPerfect users—whether On or not.
Cursor: Also called the Insertion Pointer, this denotes the place where text, graphics or any other item would be placed when you type, overwrite or insert them. This looks like a tall, skinny toothpick and keeps blinking so that you can locate it easily.
Mouse Pointer: When your mouse pointer looks like an I-beam you should be able to move it freely about the screen. This is used for either placing the cursor at the desired place (take the mouse pointer there and click) or choosing any command either from the menu or from toolbars. The mouse pointer changes shape when in the process of doing certain tasks and the cursor disappear.
Creating Documents
Word always starts by opening an untitled “normal” document so that you can begin from scratch. This “normal” document is based upon all the default values (another name for predefined setting) provided by Word i.e. standard page size, standard margins, font type and size etc. You can change these settings and create your own customized document based upon new settings. You can also save your new settings in a specific kind of file, called a Template file, which will help you to quickly create document based upon these customized settings. You can create your own letter-heads; fax sheets, invoices, memos etc. as templates pre-printed forms, all you have to do is fill in the blanks, very similar to filling in paper forms manually. Templates have been covered in more detailed later.
Tuesday, November 10, 2009
Starting MS Word
To start Word click once on the Start button, choose Programs and click once on Microsoft Office and then once on Microsoft Word.
On standing Word you would see a word main screen with the Tip of the Day (unless somebody had instructed not to do so, in the last session). These tips are Word’s way of teaching you new tricks and techniques while you work. Most of these tips are quite informative and some are even entertaining.
Read the tip, if you have the time and the inclination, then click once on Close button in the dialogue box to start working on the document.
Word Basic (Microsoft Word)
Microsoft Word is a full-featured word processing program which can be used for any work involving creating and managing text. You can use it from the simplest to the most complex word processing applications. Using Word, you can write letters and reports, prepare bills and invoices, prepare office stationary—letter heads, envelops, forms, etc, design brochures, pamphlets, newsletters, magazines, etc.
In short, you would find it extremely difficult to think of a word processing feature not available in Microsoft Word. For most tasks, Word offers several ways of doing the same thing. It is left to the user to find which one is preferable to him. Since covering all the different methods for doing the same task would require a book running into thousand pages, I have taken the liberty to illustrate the method(s) I considered most user-friendly. As you gain more proficiency in using Word you will yourself discover other methods of doing your tasks.
Monday, November 2, 2009
Troubleshooting & Checklist
Troubleshooting Checklists
The most common problem with any new PC build is partially made or improper connections. Most of the troubleshooting procedures in this blog require that the cover be removed form the PC and that some components be removed or reconnected. For this reason, it's best to plug in the PC through a switched power strip, so you can use the power strip switch to isolate the system from the electrical supply before every repair attempt.
Most people, even professional technicians, tend to get a little sloppy when troubleshooting, often accidentally introducing a new problem to replace the old. The main key to any type of troubleshooting is to go one step at a time. That way, when the original problem is corrected, you'll know exactly what did the trick, and if you create a new problem, you'll know what went wrong.
We will address five basic scenarios in this blog, ranging from a stone dead system to a lack of functionality, such as a modem that won't connect. Although these procedures will uncover most assembly errors, there is often no way to isolate a dead component without having other known good parts to swap out. In the world of professional PC troubleshooting and repair, the "swap' till you drop" strategy is still the most common troubleshooting technique employed. Swapping components requires no expensive diagnostics software or hardware and is usually the quickest way to isolate a problem. Another reason to steer clear of specialized diagnostics tools is that they are geared to identifying problems with subcomponents that can't be fixed anyway. Finding out exactly which address is bad in the system RAM or in the cache memory of a drive or motherboard is of little use when you'll have to replace the whole assembly anyway.
These troubleshooting procedures are for a newly built PC. If you have been using the PC for some time for any new problem that arises you have to consider the possibility of a computer virus. One way to check whether you have a hardware problem or a virus problem at boot time is to boot from your original operating system CD. If you do contract a virus, there are many virus doctor programs you can buy with a reasonable certainty they will fix the problem, but you may need Internet access to download the latest virus inoculations form the manufacturer's Web site.
In general, if you computer a serious recurring software problem with your PC, and you has good backups of any important data, the most reliable fix is to wipe clean the hard drive by deleting the primary partition with the FDISK program and reinstall the software form scratch. Just be really sure you have the original CDs and serial numbers for all the software you use, in addition to good data backups, because once you FDISK, it's all gone. Before running FDISK, confirm that your operating system CD will boot!
Caution: We cannot reiterate enough times that you should disconnect power from the system before making any change inside the case; then reconnect after each change to check the result. If you smell a burnt electronics odor at any time, you have a blown component and should not attempt powering up again until it is found and replaced and the cause of the failure is determined.
Stone Dead
You switch on your new system and there are no signs of life. The power supply fan doesn't turn; there are no sounds, no lights.
· Make sure the power cord is fully inserted into the power supply, the override switch on the back of the supply (if so equipped) is turned on, and the voltage switch is set correctly. Don't neglect to make sure the wall socket you are plugged into is live by unplugging the computer and plugging a radio or lamp to check.
· Recheck the motherboard documentation for the proper connection of the leads from the front panel power switch. Don't settle for just looking at the switch connection to the motherboard; remove the lead, check that the terminal block matches the documentation, and then reconnect it. Undo the main power supply connection to the motherboard (this requires pressing in the clasp as you pull gently on the connector), inspect the connector for damage, and reconnect. On Pentium 4 systems make sure you have connected the additional 12V header.
· Search for shorted components by disconnecting the power cables and ribbon cables from the drives; one drive at a time, retrying power up after each drive is disconnected. Without reconnecting the drives, remove each adapter card (leave video for last) one at a time, retrying power up after each removal.
· Remove and reinstall memory DIMMs or RIMMs, inspecting for physical damage. Remove and reinstall the heatsink and CPU, double checking the CPU fan is connected to the proper terminal on the motherboard. Never attempt to power up the system without the heatsink installed.
· In extremely rare cases, the power switch on the front panel may be faulty. You can use a continuity else that could cause a short circuit to the motherboard circuitry. Reinstall the motherboard in the case and reinstall the video adapter, then try powering up.
If you still have no power, the problem is most likely a defective power supply or motherboard.
Power Comes On; Screen Is Dead
You hear the power come on and the drives spinning up, but the screen remains blank.
· Make sure the monitor is plugged into a good power outlet by switching wall sockets with the power supply cord. If the power cord is not permanently attached to the monitor, make sure it is fully inserted in the socket on the back of the monitor. If your monitor is equipped with manual dials for brightness and contrast, make sure they are in the middle of their range.
· Remove the monitor connector form the video card and check that none of the pins in the shell are bent over. Note that some missing pins in the three-row high-density connector are normal.
· Remove and reseat the video adapter, making sure the hold down screw doesn't cause the back end of the adapter to lift partially out of the bus slot.
· Check for a defective or conflicting adapter on the bus. Remove any other adapters installed, one by one, rechecking power after each. Don’t forget to unplug the power supply, or turn off the power strip or override switch before each removal.
· Double-check the motherboard documentation for overlooked CPU selection switches or jumpers settings. Depending on the motherboard used, CPU selection might be automatic. Don’t take the manual at its word that default settings are set; check the actual switch and jumper positions on the motherboard.
· Double-check that CPU and memory modules are seated properly, particularly slot-type CPUs, which can take a good deal of pressure to mate correctly with the motherboard.
If you still have no live screen, the problem is likely defective hardware. Make sure the case speaker is properly connected to the motherboard as per the motherboard documentation. If you hear a series of beeps, note the number and sequence, s they will pinpoint the defective component. The motherboard documentation or manufacturer Web site should give the codes, although the most likely candidate for beeps on a dead screen is the video adapter. If no beeps sound, the most likely candidates are a dead monitor (easily checked by connecting it to another system), a defective motherboard, or a defective power supply. In some instances, you may have bad RAM or a bad video adapter but still not hear any beep codes.
Screen Comes On; No Boot
You get text appearing onscreen, but the PC either won’t try to boot or locks up in the process.
No onscreen messages indicating boot failure.
Enter CMOS Setup by following onscreen instructions (usually by pressing the DEL or F1 key) after power up. Select the CMOS option to Restore Default Settings or similarly phrased option, save and reboot. Note: If you cannot access Setup, double-check that the keyboard and mouse connectors aren’t interchanged. If you still can’t access Setup, disconnect power and remover all adapters except the video and disconnect the drives. If you still can’t access Setup, you have some defective hardware, most likely the motherboard, although it could still be the RAM or CPU. These core components should always be bought from the same source to simplify return issues.
If there are still no messages indicating boot failure, enter CMOS Setup again and make sure the CPU speed setting, bus clock frequency, and IDE interface speed don’t exceed your component ratings.
If the system hangs at Verifying DMI Data Pool, it is usually a motherboard or IDE device problem. If you have an option to enable Reset Configuration Data, use it. Disconnect your IDE cables from the motherboard and see if you can get as far as a Drive Failure or No Boot Device message. If not, the motherboard will probably need replacing, although you can try discharging the onboard battery first by using the jumper setting in the motherboard manual for disabling a forgotten password.
Missing operating system or no boot device message.
· Check that the IDE cables are connected to the drives and motherboard properly by removing and reinstalling them. Make sure the power connectors to all the drives are properly installed. Make sure the master / slave jumpers for the drives are installed properly.
· If the system tries to boot a CD and fails, it may just be bad timing. Strangely enough, some high-speed CD drives take so long to get up to speed that the BIOS (motherboard logic) gives up on them before they get there. If the screen displays a message such as “Insert CD and hit any key when ready,” eject the CD tray; then push it back in, but wait until you hear the drive spin up before pressing a key to continue. It might take a few efforts to get this right if it’s going to work.
· Check that the operating system CD is readable in another system, and don’t try using pirated operating system software on home recorded CDs.
· Enter CMOS Setup and rearrange the boot sequence so that the CD-ROM or the IDE channel to which it is connected is selected as the first boot device. This shouldn’t be necessary, but it will help if a previous attempt to install the operating system failed, leaving the hard drive appearing bootable to the motherboard.
· Simplify the system by removing any additional drives so all you have left are a “master” hard drive on the primary IDE channel. If it doesn’t work, as a final check try both drives on the primary controller with the CD as the “slave.”
Boots; Locks Up During Or After OS Install
Everything appears to be working fine, right up through formatting the hard drive. But, at some point during the operating system installation or immediately after, the PC locks up.
First check with your parts vendor or operating system manufacturer for known compatibility issues. Also be aware that some CDRs and combination drives have problems with operating system install, which usually manifests itself as a “read error”.
Unplug the power and remove all adapters except the video adapter. Install the operating system. Next install the motherboard drivers from the CD that shipped with the motherboard and the video adapter driver from its own CD. Install any other adapters one at a time, reconnect power and reboot, allowing the operating system to deal with them individually.
Make sure you are using the approved cabling for any high-performance parts such as 80-conductor ribbon cables with Ultra 66 or Ultra 100 hard drives, because communication breakdowns at high speeds are likely to show up under the load of operating system installation.
In some rare cases, operating system installation can fail repeatedly because a borderline component is suffering a heat-related failure as the system warms up. This is extremely difficult to troubleshoot without parts to swap out, and if you bring the parts back to the point of purchase, it might be hard to convince the vendor that the problem isn’t in your imagination. Make sure the CPU heatsink is properly installed, the heatsink fan is working, and you aren’t building the system in a hot attic in the summer. Go through the steps related to CMOS Setup in scenario 3 and document all the troubleshooting steps you go through for the vendor. Try reinstalling the operating system several times with no adapter other than video before concluding that you have a hardware failure.
Boots and Runs
If you operating system installation goes smoothly but you have trouble accessing a particular device, the problem is as likely to be software as hardware. Extensive software troubleshooting is outside the scope of this website, but we will mention some of the key points you can check in Windows operating systems.
Hard Drive
· Any message indicating a hard drive read or write failure is a hardware error. Try replacing the ribbon cable, making sure you use the newer 80-conductor type.
· Isolate the hard drive on its own IDE channel, moving any other drives to the secondary channel on their own cable or temporarily disconnecting them.
· If the hard drive is excessively noisy or makes a continual clunking sound, it has suffered internal damage and odds are even an expensive data recovery outfit won’t be able to help
CD or DVD Drive
If the drive has trouble reading a particular disc, try wiping off any fingerprints with a clean flannel shirt. Note rewriteable discs written in CDRs and DVDRs are often unreadable in other drives.
For continual read errors, try all the steps for hard drive troubleshooting new IDE cable, isolation, and swapping IDE hard drives, so isolating them on their own controller will often fix the problem.
If you can’t play music CDs even though your speakers work with other computer sounds, the thin audio cable from the sound card (or motherboard with integrated sound) to the four-pin connector on the back of the drive is improperly installed or missing.
If you record music CDs on our PC and they won’t in your stereo, make sure you are using CDR blanks, not CDRW.
If you have a CDR or DVDR and your write sessions often fail, try recording at a lower speed and make sure you are using media certified for at least the speed at which you are recording.
Sunday, November 1, 2009
Exploring CMOS Setup
When you enter CMOS Setup, usually pressing the DEL or F1 key right after the PC is powered up, you are presented with the Main Setup screen, a menu of major setup functions. The items with an arrow to the left will present their own submenu; the items without arrows fulfill a single function. One of the most important single function items is Load Fail-Safe Defaults. This option disables memory caching, high-speed drive access, and all performance enhancing features for troubleshooting. Load Optimized Defaults restores all these settings to where you really want them.
Main Setup screen
Standard CMOS Features, once the most frequented page in Setup, has lost most of its reason for existence to automatic drive detection. About the only occasion for which you might need to change settings here is if you are using a hard drive from an older system. If that's the case, before removing the drive from your old clunker, enter Setup there and write down the drive parameters and addressing mode (CHS, LBA, Large). When it's installed in your new system, select that hard drive on this screen and make sure the parameters match in the submenu (note the arrow to the left of the IDE items). If not, change from Auto to Manual and enter by hand.
Standard CMOS Setup
Although there are many user-configurable settings in Advances BIOS Features, most should be left at the default settings unless you are troubleshooting. (For example, you never want to use a PC with the Internet or external CPU cache turned off.) However, you can arrange the order in which the system will try boot devices here, particularly if you have trouble installing your operating system on a new system. It's also the place to change the boot-up status of the NUM LOCK key, which controls the numeric keypad on the far right of the keyboard and drives some of us nuts!
Advanced BIOS features
Advanced Chipset features defines how the motherboard chipset manages the onboard resources. Unless you are troubleshooting, you definitely want the system and video BIOS set "cacheable" so they can run at the speed of system RAM and not the Flash memory they are stored in. Also, if you are using Error Code Correction (ECC) memory DIMMs, you can tell the chipset how to handle error conditions; whether to stop dead and report or fix the error and continue.
Advanced Chipset features
Integrated Peripherals includes all the onboard peripheral controllers, such as the IDE controllers, USB ports, I / O ports and printer port. Generally, the default Auto selection is fine, but in troubleshooting, you may want to cut back the speed of the IDE bus (or temporarily disable DMA). You can even disable the IDE controllers entirely, replacing them with a PCI IDE controller. Note the vertical bar to the right of the menu area that indicates the whole screen isn't shown. You'll have to scroll down to get to the second serial port or the printer port.
Integrated Peripherals
Power Management encompasses not only power conservation settings but all power up and down functions. Here you can instruct the PC to come out of standby (a low power sleep mode) on modem, network, or other PCI adapter activity. You can also control how the power switch on the front panel functions, with a four-second delay or with immediate results. An important feature for servers is whether you want the PC to automatically power back up after a power outage shuts it down.
Power Management
PnP / PCI Configuration is another screen that you can leave alone if everything works, but which is invaluable for troubleshooting or getting older legacy adapters to work. You'll usually want to select PNP OS Installed (i.e., your are using a Plug and Play operating system such as Windows). If you can't get the operating system to recognize or allocate resources to an older adapter, you can allocate the resources manually here, IRQ and DMA, on a slot-by-slot basis. Also, if you try adding a new adapter to your PC and can never boot up afterward, you can try enabling Reset Configuration Data.
PnP/PCI Configuration
PC Health Status is the PC equivalent of the monitoring screens around a hospital bed in ICU, which hopefully you've only seen on TV. Not only is it helpful for troubleshooting overheating conditions and power supply problems, but it allows you to set a ceiling temperature at which the PC will shut itself down to prevent damage. The CD that ships with the motherboard usually contains a program that will display all this information from within your operating system.
PC Health Status
Frequency / Voltage Control is strictly for overclockers--techs who choose to exceed the manufacturer recommended settings for their CPUs and memory. The main dangers are overheating and instability, so the frequency control allows you to raise the basic clock speed in 1MHz increments while monitoring performance. Another side effect of overclocking can be shortened component life, though this isn't much of a concern to someone who wants the performance now. Frankly, I haven't fooled around with overclocking for more than 10 years because all the stuff seems awfully fast to me these days. 
Frequency/Voltage Control
None of the changes in CMOS Setup take effect unless you choose Save Exit, which you can reach directly from most Setup screens by pressing the F10 key. The two options on the Main Setup screen that we didn't mention are the Supervisor Password and User Password. The main reason most people might want to set a Supervisor Password is to prevent their kids from accidentally putting in a password and forgetting what it is, effectively cutting off access to the PC or Setup (password prompting is controlled by Security Options in Advanced BIOS Settings). The sole cure for a lost password is to open the PC and place the "discharge battery" or "forget password" jumper on the motherboard.
Save settings and exit
installing motherboard into the cabinet
The next steps to test fit the motherboard in the case. Use two hands to hold the motherboard over any existing standoffs and check the fit with the I / O shield. Next, count the number of silver rimmed holes in the motherboard that line up with holes in the case (all of them should). Set the motherboard off to the side on its static bag and remove any standoffs than don't line up with the holes in your board.
Installing the MotherboardInstall standoffs in the case holes that match your motherboard. Do not use standoffs that ship with the motherboard unless you remove all the standoffs that are installed in the case. Slight differences in standoff height can put unacceptable stress on the motherboard. The standoffs that shipped with this case are the standard brass type, which can be tightened with a nut driver or pliers, but don’t' over tighten or they may break.
Count the number of standoffs installed and set aside that number of screws. Reinstall the motherboard in the case, securing the corners first. It's usually best to start with the corner by the memory sockets, across from the I / O core. The little tabs on the I / O shield can apply enough spring force that you need to really keep the motherboard pushed into the shield as you install the screw. Secure the other corners, and then fill in the other screws. If you finish with one of you set-aside screws left over, remove the motherboard and takeout the standoff that didn't line up with a hole.
Here you can see I / O core of the installed motherboard properly aligned with the I / O shield. Above the I / O core are the two exhaust fans. The airflow direction can be confirmed by noting that the labels on the fan motors are visible through the grate.
The next step is to attach main ATX power connector to the motherboard. The 20-wire connector is keyed so that is can only be installed one way, and it automatically secured by the plastic spring latch. The power supply should not be plugged in or switched on until build is complete.
With the introduction of the Pentium 4, Intel required an additional 12 V lead from the power supply to the motherboard. Some P4 motherboard use an old-fashioned AT power connector to supply additional power for the CPU or AGP Pro slot, but none of our builds use one of these. We attach the 4-wire 12 V power connector next to the I / O core.
The muffin fan that we previously installed in the front of the case needs a power connection, and one is conveniently located nearby on the corner of the motherboard. Using the motherboard connection means the computer can monitor the fan status. The muffin fan in our Athlon / P4 build is powered directly from a power supply lead.
The most important of the front panel leads to the motherboard is the power switch. This two-wire connector can go on the proper two posts either way, unlike LEDs, which will only work with the correct polarity. The circular unit below and slightly to the left of the connection block is an onboard piezoelectric speaker, eliminating the need fro a case speaker connection.
Assembling P4(installing RAM)
The Intel 845GVSR motherboard supports two banks of DDR RAM for a total of up to 2 GB of memory. We are installing two piece of 256 MB DDR total 512MB. The DIMM(Dual Inline Memory Modules) are keyed with two notches so they can't be installed backward.
Spreading the DIMM Socket
Before installing any modules, make sure the white locking levers on the sides of the sockets are spread. As you seat the module by applying even pressure with two thumbs, the white levers will raise into position. This requires a good deal of pressure, so do this with the motherboard placed on its static bag on a hard, flat surface.
The second DIMM is installed in the same bank as the first, filling Bank 0 before Bank 1. DIMM modules are only 32bit wide, so it takes two modules to make up the 64-bit dual-channel memory bus width.
Seating the DIMM
Assembling a P4 (installing CPU & heatsink)
The motherboard in this build is the first to support the 2.0 GHz Pentium 4 in Socket 478. It features dual-channel RDRAM support, integrated audio, 10 / 100 BaseT networking, and five USB ports. The micro ATX layout only supports three PCI expansion slots (the vertical white slots to the bottom left), but with the integrated features and all those USB ports, that's more than enough for most applications.
Pentium 4 keyed to Socket 478
The Pentium 4 for Socket 478 is physically smaller than any of the other CPUs currently in use, due largely to the smaller dimensions employed on the silicon level. The chip is keyed to the socket with a missing pin in one corner, so it can’t be inserted the wrong way.
The first step to install the CPU is to lift the locking lever on the side of the socket. Move the lever a little away from the side of the socket to free it from the hold-down, and gently pull it up until stops. It shouldn't require any force to move the locking lever. You can actually lift it with one finger once it's past the hold-down.
Locking the Pentium 4 in place
The Pentium 4 is placed in the socket with the keyed corner, also marked by the black dot, matching the socket key. The locking lever is lowered back into the tuck position. Don't be surprised by the great change in resistance between raising the lever and lowering it. The lever locks 478 pins in place by spring force.
The Pentium 4 heatsink for Socket 478 actually consists of three pieces. The first of these, the retention module, came permanently mounted on the motherboard. The two pieces shown here are the retention clip and the active heatsink, a fan mounted on a finned aluminum structure that maximizes surface area to disperse the heat.
Lowering the heatsink adn retention clip into place
The dark area on the bottom of the heatsink is a pre-applied thermal interface, saving us from the need to apply thermal grease to the CPU package. The retention clip is placed over the heatsink and the whole assembly is lowered into the retention module. The heatsink settles over he CPU, held a slight distance above it by the pads in the corners of the retention module.
The retention clip fits loosely over he heatsink, with its four clips lined up with the four holes in the retention module posts. Push the whole retention mechanism down over the heatsink to lock the individual clips in place. These clips make an audible "click" as they are pushed over the retention module, but the whole assembly sits quite loosely.
Locking the heatsink assembly into place
The two levers that force the heatsink into contact with the CPU and lock the whole assembly into place actually move in opposite directions. Lift both levers (I do this simultaneously) and bring them all the way over until they lock down in the opposite positions. This takes even more force than the locking lever on the CPU socket.
As soon as the active heatsink is locked in place, attach the fan to the CPU fan point on the motherboard, normally labeled "fan 1." This allows the motherboard BIOS (Basic Input / Output System) to monitor the CPU fan speed and manage it in power saver and sleep modes. In this instance, the fan 1 connector was the closest connector to the CPU socket, but this isn't always the case, so check your motherboard documentation.
Connecting the CPU fan
Wednesday, October 28, 2009
collect the parts before assemblin a P.C.
The following checklist should be completed when you order PC parts to make sure you have enough components to assemble a working PC:
• ATX Case and power supply Note that both the Pentium 4 and Athlon have special power supply requirements, although many new power supplies provide for both of these.
• ATX Motherboard and CPU Socket 421, 478 or 775 for Pentium 4, depending on CPU model for Athlon or P4, Socket 370, or Slot 1 for Pentium III or Celeron.
• RAM RIMM for Pentium 4, 128MB minimum, DDR for Athlon or Duron (DDR support for Pentium 4 is expected in early 2002), for Pentium III / Celeron, 64MB SD (synchronous dynamic)
• Video 2X / 4X AGP adapter with minimum 8MB video RAM (unless the motherboard has integrated video). Make sure the AGP adapter voltage is universal (3.3V or 1.5V) or matches your motherboard requirement.
• Floppy Drive 1.44MB 3.5" floppy drive.
• Hard Drive 40 GB IDE drive or larger, ATA 100 compatible with 80-conductor cable.
• CD/DVD CD-ROM or CD recorder, DVD-ROM or combination CD-RW / DVD-ROM. Any of these can be used to install the operating system form CD.
• Keyboard Keyboard with PS/2 style connector.
• Mouse Mouse with PS/2 style connector.
• Monitor 15" or larger monitor.
• Operating system Windows or Linux on CD, any version.
RAM Details
We try to avoid giving history lectures in this website, but on the subject of memory, a brief review is essential to understanding the terminology. One of the basic innovations that made digital computers possible, Random Access Memory (RAM) allows the CPU to retrieve information stored at a specific memory address without having to read through all the memory to find it. Contrast this with a tape drive, where the whole tape may have to be wound by the read head to reach the location of the desired information. Even with the relatively fast hard drive, the read head must physically move, as much as tens of millimeters, and wait for the disk to spin until the information is under the head.
The access times of drives are measure in milliseconds, or thousandths of a second; the access time of RAM is measured in nanoseconds, or billionths of a second. When it comes to locating a single byte of data at a random location, memory outperforms other storage media by a factor of hundreds of thousands. If this wasn't the case, the super-fast CPUs would have no purpose, because they would spend all their time waiting for new instructions and data to work on.
There are two basic types of RAM in use: Static RAM (SRAM) and Dynamic RAM (DRAM). Both types of memory forget everything if the power is tuned off, but SRAM doesn't require the constant refreshing the DRAM does, ergo the names, "Static" and "Dynamic." SPRAM requires four or five times as many transistors to implement as DRAM, as it actually traps each bit of information in a structure called a flip-flop. DRAM stores a bit as a temporary charge on the leg of a single transistor, but this decays away so rapidly that it must be reread and refreshed many times per second. SRAM is used as cache memory on CPUs and in other applications, but always in relatively small amounts because of its increased power and real estate demands. DRAM is used for the main PC memory and has been since the original IBM PC was introduced 20 years ago.
Fast Page Memory (FPM) was the first big performance enhancement to DRAM, which had previously treated each new memory transaction like a surprise invitation. FPM made it faster to access data in the same memory "page" although the term "row" offers a better representation of what really goes on. When a new data bit is to come from the same matrix row as the previous bit, the memory controller needs only to increment the column location and the same row address will be used, saving an address transaction.
Extended Data Out (EDO) DRAM shortens the recovery time between sequential DRAM reads, offering about a 20 percent performance boost in overall memory throughput. EDO was backward compatible, meaning it would function in systems that were designed to support FPM RAM, albeit without any performance increase. Burst EDO (BEDO) was the next level of enhancement in which a series, or burst, of bytes from memory could be transferred to the CPU in a single request. If the CPU actually required data from these subsequent locations, an operation has been saved, and if not, nothing has been lost.
Synchronous DRAM (SDRAM) can really boost memory bandwidth through synchronization with the system clock. This eliminates a large number of timing delays, which can result in wait states on the part of the CPU (i.e., idle time). The motherboard must be designed to support SDRAM, which is not backward compatible to EDO or FPM. Early SDRAM modules were 5V devices, but the current modules require 3.3V. Fortunately, memory module designers got together earl on and came up with a standard system of notches in the contact edge of memory modules, which prevents them from being installed in the wrong type of memory socket. SDRAM was originally available at 66 MHz, but 100 MHz (PC100) and 133 MHz (PC133) devices so followed. The current speed champion for SDRAM is PC150 (150MHz) and is popular with overclockers.
Double Data Rate (DDR) SDRAM, simply known as DDR, is the next step after SDRAM. DDR can effectively double the throughput of earlier SDRAM by transferring data on both the rising and falling edges of the bus clock. The Athlon was the first CPU to take advantage of DDR, which it currently supports with a 266 MHz FSB, and the Pentium 4 is expected to follow suit. The Duron supports DDR at 200 MHz. DDR modules are known both by their MHz rating and PC nomenclature similar to the earlier SDRAM modules. 200 MHz DDR is PC1600,266 MHz DDR is PC2100, and 300 MHz DDR is PC2400. The motherboard must explicitly support DDR for it to be used.
256 MB DDR DIMM
The RAM used in the IBM PC came in the form of one bit-wide chips in Dual Inline packages ,or Dip Chips. As memory chips shrank and capacity grew, they were mounted on small circuit boards called Single Inline Memory Modules (SIMMs), first 8 bits wide (1byte) and then 32 bits wide (4 bytes). As chips continued to shrink and capacity and memory buses continued to grow, the SIMM width was doubled, giving us DIMM. The current DIMM modules are 64 bits wide, the same as the memory bus in PC systems not using RDRAM, so they can be installed singly or in any multiple.
RAMBUS or RDRAM, technology represents a departure from the step-by-step evolution of RAM we have presented to this point. RDRAM Inline Memory Modules (RIMMs) are only 16 bits wide, but they make up in speed what they lack in width. Dual-channel motherboards operate RIMMs in pairs, allowing an effective width of 32 bits at speeds of up to 800 MHz. Not surprisingly, RDRAM modules run awfully hot, and they currently cost about twice as much as DDR modules of the same capacity.
RIMMs must be installed in banks of two, and unused banks must be filled with special dummies called Continuity RIMMs (CRIMMS) for electrical signal continuity. The 800 MHz RIMM is designated PC800; there are also slower versions designated PC700 and PC600, although they are primarily used in mass-market systems.
Both DDR and RIMM modules are available with the Error Correction Code (ECC) enhancement. ECC memory can correct single-bit errors on the fly and catch multiple-bit errors, unlike the earlier parity error checking, which couldn't correct any errors or identify two-bit flips. ECC memory must be supported by the motherboard, unless it used ECC onboard technology; and the price premium for ECC memory has almost disappeared with plummeting memory price.
CD Drive (compact disk)
CD Drives
CDs were first developed by the music industry to complete with, then replace, vinyl records. The CD drives in PCs are all capable of playing music CDs without the aid of any other hardware, and most come with a headphone jack right on the front of the drive. A CD holds a three mile-long spiral of information, where the location of a particular item is measured in minutes and seconds from the beginning, as if it were being played in a stereo. The difference between music CDs, data CDs, and all the various hybrids is strictly a matter of formatting. The speed at which your computer plays a music CD is fixed to be the same speed at which stereos play CDs, and this became known as single speed or 1X. The standard CD drives in use today can read data CDs at peak of 50X or faster.
CD Drives
HDD (hardisk drive)
Hardisk Drives
The most important storage device in your PC is the hard drive. The average hard drive sold today can store as much information as tens of thousands of floppy disks, and it can find and read that information faster than any other storage device, including CDs and DVDs. The majority of the storage space on most people's hard drive is used for programs such as the operating system, word processing and database software, and games. No author, living or dead, could ever fill up a modern hard drive by writing books, but a couple hours of high-quality video would do the job. Although you can always make room on a nearly full hard drive by destroying (deleting) old programs of information, most people prefer to let the clutter build up like old boxes in the attic, simply adding a new hard drive when things get too crowded.
Although the storage provided by the hard drive is certainly permanent in comparison to RAM, it's nowhere near bulletproof. The mean time between failure (MTBF) ratings provided by hard drive manufactures are highly optimistic, and always exceed the useful life of the drive by at least a decade. Anecdotally, I would estimate that one in ten hard drives suffers complete failure within a couple years of being purchased, with an even higher rate in notebook computers. These failures can result from all sorts of environmental issues such as excessive heat, power spikes, or the PC getting thumped at just the wrong moment.
For this reason, anybody who uses a PC for more than games and Internet surfing should get in the habit of making copies of important information, a process known as "creating a backup”. Creating a backup can be as simple as copying your checkbook register or word processing documents to a floppy disk once a week, but never use the floppy disks to exclusively store documents in place of the hard drive because they are far less reliable, not to mention much slower.
Hardisk DriveIn critical business applications, a special technology called RAID (Redundant Array of Inexpensive Drives) provides a means to duplicate data across several hard drives to increase performance and protect against the failure of any individual drive. RAID solutions usually provide automatic fail over, so you won't experience any down time if a single drive fails in the middle of the business day. We will give an example of a simple RAID sub-system in our Pentium 4 build.
RAID provides no protection against fire, theft, data management errors, or computer viruses. Tape backups are the dominant devices for backing up large amounts of data, although DVD recorders and new high-capacity cartridge drives from Iomega might pick up some of the load. CD recorders, also know as burners, provide an excellent option for data backup if you organize your files on the hard drive so you know what to copy to the CD.
RAM (random access memory)
Random Access Memory (RAM) provides the fast, temporary storage from which your CPU draws the data it needs to operate. The storage capacity of RAM is measured in megabytes (millions of bytes). You'll want to build your new PC with an absolute minimum of 64 MB of RAM. If you are running very demanding applications or high data throughput jobs like video editing, you might want to install as much memory as you can afford. Currently, 256 MB is a pretty healthy amount, and is more than is included in most PCs sold in stores.
There are three basic families of RAM in use today, and we give an example of each with our three builds. The Dynamic RAM (DRAM) that makes up the system memory actually starts to forget everything many times a second, but a dedicated memory controller endlessly reads and writes this information to keep it fresh. Memory, amusingly enough, does forget everything the moment the PC is turned off, which is why we have hard drives, CDS, and floppies to provide storage. The fastest way to tip off a showroom vulture that you are a little hazy about computer terminology is to refer to "the memory in the hard drive."
CPU (central processing unit)
The CPU is the brain of your PC, executing the instructions of the software programs you run, such as Windows XP, Linux, Word, and Quicken. Most PCs are referred to by their CPU and speed, such as a "2GHz Pentium 4" or a "1.4GHz Athlon." Currently, all CPUs being manufactured for use in PCs run at speeds from a minimum of 500 megahertz (MHz) to more than 2 gigahertz (GHz), where hertz (Hz) expresses the number clock cycles the CPU steps through in one second.
If you should as, "What can a CPU do in a single step?" the answer is "It depends on the CPU." All CPUs can actually do several things at the same time, and the designers squeeze every drop of performance they can out of a clock cycle. Although it's no longer true that equivalent speed ratings for Intel and AMD CPUs express equivalent performance, the numbers are valid for comparing performance within a family of CPUs. Thus, a 2 GHz Pentium 4 can execute 33 percent more instructions/second than a 1.5 GHz Pentium 4. We'll talk more about how the speed of the CPU impacts the overall performance of the PC in the next chapter.
Intel Pentium CPUOne of the biggest bottlenecks to CPU performance is memory speed. These huge numbers for CPU speed we are casually throwing around don't mean much of anything unless the CPU can be supplied with instructions to carry out and data to operate on. To minimize the amount of time CPUs spend waiting for memory, small amounts of super-fast memory called cache are included in the CPU package. The Athlon has the biggest cache at 384 KB, followed by the Pentium 4, the Pentium III, the Duron, and the Celeron. Depending on the type of work the CPU is doing, it might find as much as 90 percent of the data it is looking for in cache. Considering that the CPU cache is likely to amount to less than 1 percent of the total system memory, that's pretty good hit rate.
Tuesday, October 27, 2009
SMPS
The case is almost universally sold with the power supply installed and included in the price. You can build a PC on a workbench without a case (technicians often do this when testing parts), but it takes up a lot of space, interferes with the radio, and is awfully hard to pick up and move in one trip. The function of the case is to house all the parts that make up your PC, provide ventilation for the heat they generate, and protect the local environment from radio frequency interference.
Computer parts are sold as being FCC Class A or B approved. Class A is for business use, the Class B rating meets more stringent limits for residential use. Assembling a collection of approved parts is no guarantee that the completed computer would pass an FCC test suite for one rating or the other, but as a home hobbyist, you aren't required to have your computer tested. However, if you decide you love building PCs so much that you want to go into business selling thousands of them, you'll want to buy partially assembled or packaged systems that come with an FCC approval sticker.
Power supplies are equipped with a 115V/230V switch, so they can be set to 230 volts for Europe and most other regions of the world that don't use the U.S. standard 115 VAC distribution system. Just a few years ago, this 115 or 230 volts was wired directly to the switch on the front of the PC, like the switch on a lamp or a toaster oven. However, in all new PCs, the high voltage never leaves the power supply. The switch on the front panel is really just a logic switch that closes a circuit on the motherboard, which tells the power supply to come on at full power. The power supply is always providing a trickle of current to the motherboard to enable this "wake up" logic, whether the signal is generated by the power switch or by incoming traffic to the modem or network card.
ATX Power SupplyThe second function of the power supply is to generate a cooling airflow for both itself and the other parts in the case. This fan in the power supply is thermion source of noise coming from most PCs. The manufacturers of the newest high-speed components often recommend that you include additional fans in the case of increase the cooling airflow. The most common location of a single additional fan is at the bottom of the front of the case, to draw in air. A second fan can be added under the power supply at the back of the PC to exhaust more hot air. The goal is always to increase the airflow through the case, not just to blow hot air in a circle, so don't install several fans to draw air into the case and none to exhaust it, or vice versa.