its not video hardware its a software issue. you must have not reinstalled your video drivers.
go to the site and download the newest video drivers.
if you have an nvidia card (gforce, TNT, Quadro, or integrated nforce mobo) go to http://nvidia.com/content/drivers/drivers.asp
If you have an ATI card (Radeon, All in Wonder,FireGL)
download the new catalyst drivers at http://ati.com/home/online/CatalystCCCdriver.html
if you dont have a card from either of these manufacturers replace it with one cause their the only companies that have decent cards.