I am running a :

AMD 1700XP
Gigabyte GA-7VA 8x 333 board
384DDR PC2100(Crucial Mem)
Geforce2 GTS 64DDR w/ TVout
Sound 5.1
Lan, etc.
OS Windows XP Professional ED. SP1

Anyways, about 2 weeks ago my computer locked up and the screen became distored. Then when i went to reboot, my keyboard didnt work. Now my keyboard is fried and doesnt work on any computer. But my main concern is that everytime my computers on for about 20 mins it locks up and the screen becomes distorted with colors. So i thought the graphics card went bad maybe, so i install a spare ATI XPERT 128 PCI and it worked fine, except for when the screen saver came on it would lock up overnight. Now i have taken the screen saver off and it never locks up and runs fine everytime...But the only other problem is, is that when i go to run games it locks up on games it used to be able to run and also will not install any driver for the card. Error message sayin this is not the card installed on this system

So really i need to figure out what is good and what is bad or what is going on...i'm thinking about reformating tonight and seeing what happens with the old Geforce2 in there. PLEASE HELP!

Check temps. Really sounds like a heat problem.

"Error message sayin this is not the card installed on this system"

I would believe that! Try to determine the correct driver.

i have had this problem, i reinstalled windows xp pro doing a repair and problem went away, try running 3dmark2001se benchmark and see if it locks up on any of the tests, and also have you got direct x9 installed, this can cause this problem too, direct x9 should never be installed as it is very hard to uninstall (but can be done)and only the newer graphic cards support it