7800GS is compatible with an AGP 8X slot. You will need to ugrade to a beefier PSU if you install one of those cards.
Personally, I'd purchase/build a new computer with a ''PCI Express X16'' slot before dumping $250-300 into an AGP card and $50-100 into a good PSU.
I'm looking to buy a new AGP video card for my 1st Gen Dell XPS. I currently have an Nvidia Geforce FX 5200 and I was planning on upgrading to the 7800GS. Is anyone sure this will or won't be compatible? Also, if anyone has any other suggestions, I will consider them.

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