|If you did a clean install of Windows, did you install ALL the motherboard drivers?|
Have you checked "Device Manager" to determine if any of your hardware is missing a driver?
Did you format the partition (before the clean install), or delete it and create a new one? Windows XP's install disk seems to have a problem with it's format utility. Sometimes you still have remnants of data, left over from the previous installation of Windows. These remnants can cause all sorts of problems.
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