Guys is there any comparison for all new graphics cards, even if from different companies, thus we can see a list which puts cards in order?

For CoD: Black Ops, the system requirements are 256MB NVIDIA® GeForce® 8600GT / ATI Radeon® X1950Pro or better
my question is would a HD4650 1GB DDR2 run the game on max resolution, I mean its 1 GB and the game needs 256 MB

and would a 9600 GSO 1.5GB DDR2 make the same performance as 8600 GT?

what about crysis using the 9600 GSO?
I'm not that good in computer.
Don't forget about price lol
Well, the graphic card power is not only measured by how much big is the memory store. Go with an Nvidia GTS 250 and you'll be happy.