Can i play gears of war PC with an 8500gt 256mb video card & i need video cards that can fit a slimline?

im using a slimline PC so the highest card i have is an 8500gt video card. gears of war needs a 6600 or higher... but i just wanna know how bad/good gears can play on an 8500gt. oh yahz, what kind of video cards can be used with a slimline? gimme the cards so i can check em out too!|||It'll run fine.