Kruzin is right on suggesting a cheap PCI video card. If your mobo has onboard video also, might be a matter of enabling it with the TNT card.
Proprietary systems like E machines disable the onboard video if you use a video card, but my MSI board uses both at the same time.
Heck, you could shop around for a dual VGA PCI video card, and use the onboard video to
go for a triple