i would suggest getting a nvidia card. a nvidia card within your price range would be the 6800.
AMD Athlon 64 3700+, 939pin, San Diego, 90nm
Shuttle SN25P (350 watt psu, nvidia 4ultra mobo)
CORSAIR ValueSelect 2x512 DDR400 PC 3200
Seagate Barracuda 80GB Sata150
Powercolor Radeon X850XTPE, PCI-E
PLextor PX-740A DVD Burner
Sony Floppy Drive
First off will the 350 watts be enough?
Second the mobo has sata but will it be compatible with 150?
Next what is the best gcard at about $250 as I think the x850 will most likely be overkill.
And lastly does the system components seem to be compatible?
Thank you all for your help.

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