if you game at less that 1680x1050 (20" widescreen) then an 8800gt will be fine for every game except crysis if you can do without anti-aliasing, high anistropic filtering, hdr lighting, etc. a 9800gtx will make a difference at high resolution and with the extra eye candy turned on.
-NZXT Adamas Gaming tower
-650W Corsair CMPSU-650TX Power Supply
-Intel Core 2 Duo e8400 (2x 3.0Ghz/6mb L2 Cache/1333FSB)
-Asus Silent Knight AL CPU Cooling Fan
-2 Gb DDR2-800 PC6400 RAM
-320GB hard drive
-20x dual format, double later DVDr/rw CDr/rw drive
-3D Premium surround sound onboard
-XP home edition w/ SP2
-Asus P5N-D Nvidia nForce 750i SLi chipset
The main question, I think, is the video card. I'm looking to play Spore, Warhammer Online: Age of Reckoning, Battlefield: Heroes. I'd also like to be able to play games like Crysis/Far Cry 2, although I'm fine with playing those on medium settings or at lower resolutions.
The video cards I am considering are:
eVGA 8800GT 512mb (and maybe buying a second one for SLi mode later)
eVGA 9800GTX 512mb (and if going SLi, only a ways down the road)
Is the 9800gtx worth the extra money? Is it necessary to run games like Spore/WAR? Or will I only really see a difference in shooters/other games with high end graphics?