- Delete any unused or unnecessary programs and files. These may be taking up space, memory and resources, thus slowing your computer. Also delete your cashe/ temp files, empty your recycle bin, clear your internet browsing history, etc.
- Defrag your drive. HD Fragmentation causes slows, program hangs, freezes, etc. Diskeeper is a great defrag product. You can download free trialware at http://www.diskeeper.com
– Clean your registry. Your registry holds all the information regarding updates, installs, uninstalls etc. so this needs to be cleaned. This will optimize and remove redundant or unwanted items.
References :

1. De-Fragmenting
Over time, the data on your hard drive gets scattered. Defragmenting your hard drive puts your data back into sequential order, making it easier for Windows to access it. As a result, the performance of your computer will improve.
a) Right click of C Disk.
b) Click properties.
c) Click tools tab.
d) Click "Defragment now".
e) Click Defragment.

2. Uninstall Unneeded Programs
Removing programs that you no longer use can free up space on your computer and speed up your system’s performance. However, you need to uninstall the programs properly to see much improvement; deleting them is not enough.

3. Stop Programs from starting on Windows boot
One way you can speed up your computer is to prevent programs from launching themselves at start-up. Not only do the unwanted programs delay the start of Windows, they also continue to slow down your computer since they use system resources.
a) Open your Start menu.
b) Click Run
c) In the command screen type "msconfig.exe"
d) In the "system configuration utility", click either "service" or "startup" tab
e) Uncheck all programs that you are no longer using.
f) Click "OK"

4. Check for Spyware and Adware
Spyware is software that allows companies to monitor what websites you visit or even access your computer. Adware is software that displays advertisements. Both use system resources and slow your computer down. Detecting and removing the programs will improve system performance.
Get the best one from: http://toptenantispywareviews.com to scan your pc

5. Clean your Registry
Microsoft Registry Problems = Slow Computer!
Use the tool: http://toptenantispywareviews.com/Clean_Up_Center.htm
Learn more information "why is my computer running so slow": http://toptenantispywareviews.com/RegComputerSlow_why.htm
References :

First, if you haven’t cleaned your registry in a while. This is necessary. Your registry holds all the information regarding updates, installs, un-installs etc. Each one of those events produces a key. That key needs your PC’s resources and free space. So, if you clean your registry, you make more resources available for speed. Do a registry scan if you got more than 20 errors you should clean it.
http://www.delete-computer-history.com/what-is-the-best-registry-cleaner.html

2. Clear your Windows cache files, this is your temporary file. It can grow up to a large volume and stop your computer from using RAM properly. In a sense slow it down by preventing it from using free space.Here is how:

1. Quit Internet Explorer, Firefox, or any other web browser
2. Click Start, click "Control Panel", and then double-click "Internet Options".
3. On the General tab, click "Delete Files" under Temporary Internet Files.
4. In the Delete Files dialog box, click to select the "Delete all offline content" check box , and then click OK.
5. Click OK.

3. Manage your startups. Your excess CPU usage is due to too many programs running in the background. You can cut these to barebones by alter your msconfig. Here is how:

1. Open your Start menu.
2. Click Run
3. In the command screen type "msconfig.exe"
4. In the "system configuration utility",click either "service" or "startup" tab
5. Uncheck all programs that your are no longer using.
6. Click "OK"
References :

Optimally, you should format your hard disk and reinstall windows but that’s sometimes not practical so

If you have many programs running at startup install the ones you don’t need as theses REALLY SLOW YOUR PC DOWN

in plain English:

look at the taskbar, the blue strip at the bottom of your screen, if you have several icons next to your clock ( on the far right) then you need to unistall as many of these programs as possible.
References :
Personal experience

Scott

Computer Help Services
http://www.facebook.com/home.php#/group.php?gid=54828745608
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