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Poor performance

User complaints are few when people get new computers. They start up quick, and programs seem to open in a snap. But over time, the systems can slow down or hang up often. While the possibilities for system slowdowns are endless, here are a few troubleshooting areas you might want to examine before you suggest an upgrade.

Bad RAM:

Several situations can lead to a bad RAM problems on a certain machine:

RAM timing is slower than optimal machine spec.
RAM has minor flaws that only appear on detailed testing.
RAM is overheating.
In the days of Fast Page RAM, buying new RAM for your computer was a pretty simple affair. You just needed to know what speed your motherboard supported and the maximum each slot would take. Today, there are many different speeds of RAM, and the better motherboards may be tolerant of using RAM that does not match the motherboard’s maximum specs. For example, your motherboard may support PC133 RAM but will still work with PC100 RAM. But be aware that you may see performance decreases if you install RAM that is slower than the maximum spec.
Some motherboards will even allow you to mix speeds but will default to the slowest RAM installed.

Minor flaws in RAM chips can lead to system slowdowns and instability. The least expensive chips often have minor flaws that will cause your system to slow down or Blue Screen once in a while. Although built-in mechanisms may allow the system to keep working, there is a performance loss when it has to deal with flawed RAM chips

In the past, no one worried about RAM chips getting hot, because they didn’t seem to generate much heat. But that’s changed with newer RAM types, especially SDRAM. To check for overheating, open your computer’s case, power down, and pull the plug out. Ground yourself and touch the plastic on one of your RAM chips. They get quite hot. If you find that your RAM chips are overheating, you should consider buying a separate fan to cool your memory. If your motherboard doesn’t support a RAM fan, you might be able to get enough additional cooling by installing a fan card that plugs in to a PCI slot.

Another RAM-related problem may occur if you add more than 64 MB of RAM to a system that doesn’t support caching of more than 64 MB of system memory. The system’s performance will slow down when it accesses the uncached memory. For example, some motherboards completely disable the onboard L2 cache when more than 64 MB of RAM is installed, causing major performance loss.


There are many signs of impending failure before a hard disk finally crahes on you. Some of these signs may be:

Slow access times on the affected drive.
An increasing number of bad sectors when running scandisk and chkdsk.
Unexplained Blue Screens.
Intermittent boot failures.
Detecting a failing hard disk can be tricky because the early signs are subtle. Experienced computer professionals can often hear a change in the normal disk spin. After the disk deteriorates further, you’ll see the system crawl to a standstill. Write processes will take a long time as the system tries to find good blocks to write to. This performance slow will occur when using NTFS but FAT systems will likely bring you that lovely Blue Screen of Death.

When you notice the system slowdown, run scandisk or chkdsk, depending on your operating system. If you notice a bad sector where a good sector existed , that’s a clue that the disk is going bad. Back up the data on the disk and prepare for it to fail soon. Make sure you have a spare disk ready so you can replace it when it fails, or, even better, replace the disk as soon as you notice the early signs of failure.

Disk noise and scandisk/chkdsk are your best indicators for identifying a failing drive that’s leading to a system slowdown.


BIOS settings are often an ignored culprit of system slowdown . Most people accept the BIOS settings as they were configured in the factory and leave them as is. However, slowdowns may occur if the BIOS settings do not match the optimal machine configuration. Often you can improve machine performance by researching your motherboard’s optimal BIOS settings—which may not be the same as the factory defaults.

There is no centralized database of optimal BIOS settings, but you can employ a search engine such as Google or AllTheWeb and use your motherboard name and BIOS as keywords to find the correct settings.


You’ve just added a new UDMA-66 disk drive, and it doesn’t seem any faster than any of the other drives in your machine. So what’s the problem?

It could be that your motherboard doesn’t support the UDMA 66 specification. Check your manual to determine what type of IDE interface it supports. If the motherboard only supports UDMA 33, then your UDMA 66 throttles down for backwards compatibility. You can get around this problem by installing a PCI UDMA 66 add-on card and plugging the new drive in to that interface.

Another potential problem may be the cable type you are using. UDMA 66+ drives require a different cable than older drive types. The drive may not work at all with the old cable type. Aged cables will break down over time, especially if they are tightly folded and the temperature of the case remains consistently high. It’s always worthwhile to change out the drive cable to see if performance improves.


Runaway processes take up all of the processors' cycles. The usual suspects are badly written device drivers, and old software installed on a newer operating system. You can identify a runaway process by looking at the process list in the Windows Task Manager . Any process that takes almost 100 percent of the processing time is likely a runaway process.

To bring up the Task Manager to identify processes that are slowing the system, hit the keys: Ctrl + Alt + Delete. Tap these keys until it appears on your desktop.

On a smoothly running system, the System Idle Process should be consuming the majority of the processor cycles most of the time. If any other process were to take up 98 percent of the processor cycles, you might have a runaway process.

If you do find a runaway process, you can right-click the process and click the End Process command. You may need to stop some processes, such as runaway system services, from the Services console. If you can’t stop the service using the console, you may need to reboot the system. Sometimes a hard reboot is required (Turn your computer off-->wait--> and on).


As files are added, deleted, and changed on a disk, the contents of the file can become spread across sectors located in various regions of the disk. This is file fragmentation.

Disk fragmentation can significantly slow down your machine. The disk heads must move back and forth while seeking all the fragments of a file. A common cause of disk fragmentation is a disk that is too full. You should keep 20% to 25 % of your hard disk space free to minimize file fragmentation and to improve the defragmenter’s ability to defrag the disk. Thus, if a disk is too full, move some files off the drive and restart the defragmenter.


Have you ever visited another user’s desktop and noticed a dozen icons in the system tray? Each icon represents a process running in either the foreground or background. Most of them are running in the background, so the users may not be aware that they are running 20+ applications at the same time.

This is due to applications starting up automatically in the background. Look first for such programs in the Startup folder in the Start menu. Many applications place components in the Startup folder to run in the background. Some of these, such as the Microsoft Office Findfast, can really chew up processor and disk time and noticeably slow down a system. Review each of the entries in the Startup folder and delete any that are unnecessary.


Some file systems work better than others for large disk partitions. If the machine runs Windows 2000, or Windows XP, you should use the NTFS file system for best performance.

File system performance is closely related to cluster size and the number of clusters on the disk. NTFS file systems will bog down if you have a 60-GB hard disk configured with a cluster size of 512 bytes. This creates an enormous number of clusters, which the file system must track and seek. This becomes especially a problem when the drive is highly fragmented. One solution is to use larger cluster sizes. If you set the cluster size to 4K or larger, you will see noticeable improvement in file load times. Please note, however, that large clusters can significantly increase the amount of cluster slack space and lead to a lot of wasted disk space.

If you are not using the NTFS file system, you may be able to improve performance by moving files and folders out of the root directory. With FAT partitions, you may notice a big slowdown in system performance after running scandisk because a large number of .chk files are placed in the root directory. Users sometimes fill their root directories by making it the default file storage location. Move as many files and folders as possible out of the root directory, and performance should improve significantly.


Modern processors generate a lot of heat. That’s why all processors require some sort of cooling element, typically a fan of some type. When the processor temperature goes over spec, the system can slow down or run erratically. The processor fan may fail for several reasons:

Dust is preventing the fan from spinning smoothly.
The fan motor has failed.
The fan bearings are loose and “jiggling.”
Often you can tell if there is a fan problem by listening and/or touching the computer. A fan that has loose bearings starts jiggling and vibrates the case, making an identifiable noise. You may barely notice the noise at first, and it’s common for even the experienced computer professional to overlook this change. But as time goes by, the sounds and vibrations will become so prominent that you’ll change the fan out just to stop the racket.

You don’t always need to replace the fan. If it is covered with dust, you can often spray away the dust with compressed air. Note that even though you might get the fan running again, its life span has likely been reduced because of the overwork. You should keep an extra fan in reserve in case of failure, if possible.

HARDWARE FIRST: When troubleshooting a system slowdown, you should always look for potential hardware problems first. Then, investigate the common software problems. If you use a systematic troubleshooting plan, you should be able to improve the performance of most computers suffering from system slowdown.


Norman, 2002

Last Update: 17 October 2002