a 7800GT will do the job na seguro... 
actually a 6800Ultra needs a A64 3700+ & above to fully utilize the GPU's total bandwidth..
and you need atleast an A64 X2 4400+ for the 7800GTX..
..pero sa mga links na binigay mo at ni scrambler, wala masyadong difference ang 3000+ compared sa 3500+ while using a 7800GT.

...so at this point what i need really is a faster videocard para maangat ko ang quality settings like AAx4 @ 1280x1024 or setting softshadows on sa f.e.a.r and using the dx9 path sa call of duty2 @ 1280x1024

from xbitlabs...

so para umabot sa 43fps ang f.e.a.r. kailangan ko lang ng 7800gt... from 3000+ up to a fx57, the processor does not make a difference on fps

...i'm at the 20's to 30's kasi e using a 6800 & 3000+, 1024x768, medium graphics settings sa mga areas na malaki at maraming objects and kalaban, if kaya ng 7800gt gawing 43, then thats a good boost in gameplay na, considering na max detail settings nila ginawa ang benchmark...