Custom build computer means nothing. You have to give us a hint.
Motherboard Brand and Model?
Video Brand and Model?
Dont give a website just say what hardware you have
The OS may help also.
I just reloaded Vista on an old intel motherboard DG35EC with an E7200 CPU on an integrated VIDEO on the motherboard and everything works fine. No problems.
i have had trouble finding driver software for my homebuilt computer with vista.any suggestions?

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic