Windows comes with many utilities and settings that you can use to keep your system running at top performance. In this lesson, you'll learn about some of them, and you'll have a chance to try them on your own computer.

Check a Drive for Errors

Disks can sometimes develop errors in the way the files are stored, and those errors can affect system performance. Disk errors sometimes manifest themselves in odd ways -- everything from missing files to out-of-memory errors.

The primary cause of these errors is abnormal or improper shutdown -- in other words, shutting off the computer's power or restarting the system while a program is in use. unexpected shutdowns aren't always your fault, of course; sometimes a power outage occurs or Microsoft Windows locks up.

There are two types of errors a disk can have: physical and logical. A physical error is a bad spot on the disk, usually caused by physical trauma such as dropping the computer while it's running. A logical error, which is much more common, is an error in the table of contents of the disk's storage system. The Check Disk utility in Windows XP can fix both types.

If you're having problems with your computer, it's a good idea to run Check Disk to make sure a disk error is not the root of the problem. You might also run Check Disk every month or so as routine preventive maintenance.

To check a disk for errors, open the My Computer window. Right-click the hard disk (or one of them, if you have multiple) and select Properties. On the Tools tab, click Check Now to open the Check Disk dialog box, shown in Figure 5-1.

Figure 5-1: Check Disk Main (C:) dialog box.

There are two options available:

• Automatically fix file system errors: If you mark this, Check Disk fixes any problems it finds rather than prompt you about each one. Beginners should mark this; advanced users who are curious about what errors are found should not.
• Scan for and attempt recovery of bad sectors: If you mark this, Check Disk does both a logical and a physical test. Because each physical test takes a long time (an hour or more in some cases) and because physical errors are less common, most people use this option only occasionally (once every few months or so) or only if a disk read or write error has occurred.

Click Start to begin the check. If you didn't mark the Automatically fix file system errors checkbox, and if any errors are discovered during the check, a dialog box appears asking whether you want to fix them. Click Yes to fix each error.

If you see a message that the disk can't be checked now because it requires exclusive access, click Yes to schedule a start the next time you start your computer. Then restart (Start > Shut Down > Restart).

The storage system on a hard disk is not physically sequential. Files are stored in any available physical area, and the file allocation table (or MFT) keeps track of where each piece of the file resides. Then, when Windows calls for a file, it looks up the location of the file or the locations of the pieces of the file, and then puts the pieces together in memory.

When you initially write a file to disk, it's stored in one contiguous mass, but as you edit the file, the file can become fragmented (that is, pieces stored in nonadjacent spots). As you can imagine, it takes longer to open a fragmented file than an unfragmented one, because the hard disk's read and write head must hop around on the disk, picking up the pieces of the file. That's why defragmenting a hard disk improves its performance. Defragmenting a hard disk rearranges the files stored on it so that each file is stored in a contiguous area.

Defragmenting takes a long time, so you might want to begin it before you go to bed or go out for the evening and let the program run while you're away.

Don't use your computer while it's being defragmented, because every time the content of the hard disk changes, it has to start all over again. Disable your screensaver and antivirus program before running the defragmenter to minimize restarts due to hard disk changes.

To defragment a disk, you can either start from the Tools tab for the drive (right-click the drive in My Computer and select Properties) or you can select Start > All Programs, Accessories > System Tools > Disk Defragmenter . The Disk Defragmenter dialog box, shown in Figure 5-2, appears.

Figure 5-2: Disk Defragmenter dialog box.

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Select the drive you want to defragment, and then do one of the following:

• Click Defragment to start defragmenting the drive now.
• Click Analyze to check how badly the drive needs to be defragmented.

If you do the latter, a recommendation appears after a minute or two. From there, you can select whether to defragment.

Defragmenting is a good thing, but some people go nuts with it and defragment every week. That's excessive. Once every few months is okay, and if you forget, that's okay too. You probably won't notice a dramatic difference in system performance between doing it and not doing it.

Windows has two utilities for cleaning up your system. Disk Cleanup finds and deletes unnecessary files from your hard disk, freeing up overall disk space, and the Desktop Cleanup Wizard eliminates unused shortcut icons from your desktop.

Disk Cleanup recommends that you delete certain files to help you free up space on your hard disk. It might recommend, for example, that you empty your Recycle Bin, delete temporary internet files, and delete some leftover temporary files from your word processing program.

As an application operates, it sometimes creates temporary files, like scrap pieces of paper on which it jots down notes. When the application exits, these files are deleted automatically. However, if it terminates abnormally, the temporary files remain on your hard disk taking up space.

There are two ways to start Disk Cleanup. You can either go through the menu system or go through the Properties dialog box for the hard disk.

• Menu method: Select Start > All Programs > Accessories > System Tools > Disk Cleanup. In the Disk Cleanup dialog box that appears, select the drive you want to clean up.
• Properties method: Open My Computer, right-click the drive and select Properties. On the General tab, click Disk Cleanup.

Either way, you end up in the Disk Cleanup dialog box, shown in Figure 5-3. A report appears for the selected drive showing which files Windows thinks can be safely deleted. Mark or clear the checkbox for each category of files that Windows presents, click OK, and then click Yes.

Figure 5-3: Disk Cleanup for MAIN (C:) dialog box.

Repeat this process for each hard disk on your system if you have more than one.

Whereas Disk Cleanup actually frees up space on your drive, Desktop Cleanup doesn't delete anything. Instead it takes unused icons on your desktop and moves them to a folder, reducing the clutter on your desktop.

How did those unused icons get on the desktop in the first place? Well, many applications that you install place icons for themselves there automatically, and most computers come with unnecessary icons preinstalled on the desktop as part of the computer company's marketing agreements with other companies. (Don't you just hate that?) Also at some point, you may've accidentally dragged icons from a file management window to the desktop.

Every 60 days, a reminder appears in your system tray prompting you to run Desktop Cleanup. If you see such a reminder, you can click it to run the program. Otherwise, you can run it manually:

1. Right-click the desktop and select Properties.
2. On the Desktop tab, click Customize Desktop. The Desktop Items dialog box appears.
3. On the General tab, click Clean Desktop Now. The Desktop Cleanup Wizard starts.
4. Click Next to continue, and then on the Shortcuts screen, mark or clear the checkboxes for each desktop shortcut. Next to each shortcut is the date on which it was last used; items that have never been used are marked by default, as shown in Figure 5-4.

Figure 5-4: Use the Desktop Cleanup Wizard to tidy up the desktop.

5. Click Next, and then Finish. You're done.

When you finish, a new folder icon appears on the desktop called Unused Desktop Shortcuts. It contains the removed icons. You can open this folder at any time and drag one of the icons back to the desktop.

All the little graphical flourishes in Windows XP help make it more fun to use, but they also make the CPU (central processing unit) and video card work harder. For example, have you ever noticed how when you open a menu, it doesn't just appear -- it sort of fades in? Or how when you move the mouse across the desktop, it looks like it has a faint shadow behind it? Those extra niceties aren't free -- they cost you in terms of memory usage.

So let's say you want to have the leanest, meanest computer possible, eliminating every unnecessary extra that could slow it down. In the following sections, you find out which Windows settings can make that happen for you.

Display performance is the display's ability to keep up with the commands it gets from the operating system. For example, have you ever seen the screen "paint" itself, from top to bottom, a few strips at a time? Or has a video clip in a game or other application ever been choppy? These are examples of poor display performance.

Resolution and Color Depth

The resolution is the number of pixels that make up the display. The more pixels or dpi (dots per inch), the finer the level of detail, and the smaller everything appears on-screen. For example, at a high resolution such as 1280 x 1024, all of the icons on the desktop appear very tiny, whereas at a low resolution such as 800 x 600, they appear much larger. The reason is that an icon, a menu, a character of text, and so on is a precise number of pixels in size. When the pixels are smaller and closer together, the object looks smaller. The Windows desktop, on the other hand, always expands to fill the entire available screen space; it doesn't have a fixed size.

High-resolution display modes may be enjoyable to use, but if you have an old or cheap video card, your computer may not run as well in a high-resolution display mode as in a lower mode. For an old, slow computer, switching to 800 x 600 can provide a small performance boost. (You probably won't notice a difference on a new, faster computer.)

In earlier versions of Windows, the lowest resolution was 640 x 480, but in Windows XP, the lowest resolution is 800 x 600.

Color depth is the number of colors to select from for each pixel. The higher the color depth, the more unique colors you can display at once on-screen, and thus the better your photographs and graphics will look. Color depth is measured in bits. For example, 4-bit color depth provides 16-color choices because 16 combinations are possible with a 4-digit binary number (2 to the 4th power). The Windows XP default is 32-bit color, which results in a very good quality display.

On an old, slow computer, you may be able to get slightly better video performance if you decrease the color depth to a Medium setting (16-bit or 24-bit) instead of the default 32-bit.

To adjust the resolution and color depth, right-click the desktop and select Properties, click the Settings tab, shown in Figure 5-5, and then change the resolution and color quality settings. Click OK.

Figure 5-5: Display Properties Settings tab.

If this is the first time you've selected that particular resolution or color depth, a dialog box appears asking you to confirm whether the new mode works. Click Yes within 15 seconds or the display will revert to the previous settings.

Visual effects are those flourishes mentioned earlier, such as having a shadow behind the mouse. For best system performance, you should turn most of them off. (On a new, high-performance computer you won't notice much difference, so if you like them, by all means leave them turned on!)

To control the visual effects, follow these steps:

1. Right-click the desktop, select Properties, and then click the Appearance tab.
2. Click the Effects button to open the Effects dialog box, shown in Figure 5-6.

Figure 5-6: Effects dialog box.

3. Turn off any effects that you think you can live without. The more you turn off, the better your display will perform.

The Large Icons and Underlined Letters options do not have much effect on display performance one way or the other, so adjust these to your preference.

4. Click OK to close the Effects box, and then OK to close the Display Properties box.

Desktop Background

The background is the big flat area behind everything else, where the Recycle Bin and perhaps other icons sit. By default, it contains a wallpaper of grassy hill and blue sky. Wallpaper is a bitmap image; you can use any image you like here, or you can turn off wallpaper altogether and use a solid color.

Performance-wise, it's better to use a solid color than a picture. It doesn't make a huge difference, but if you're using an old, slow computer or if you're accessing it remotely (through the Remote Desktop feature in Windows XP Professional, for example), you may notice a small performance boost with a solid background.

To change the background, right-click the desktop and select Properties. On the Desktop tab, select None to remove the wallpaper. Click the Color button to open a palette from which you can select the desired color. If you don't like any of the colors, click Other to open a dialog box with a larger assortment. When you're finished, close all dialog boxes by clicking OK.

Moving On

Throughout this course, you've learned about various ways you can maintain your system on a regular basis, such as checking for viruses, making backups, defragmenting, checking for errors, and so on. Be sure to do the assignment and quiz, and visit the Message Board.

In Lesson 6, you'll learn how to create a workable schedule for coordinating all these maintenance activities so that they don't take up too much of your time.