GTX 285/AMD 6400+

Yes it would. Look at the HD 5850. It's cheaper and faster then the 285 but not till you upgrade that processor

This isn't for me, but for a fellow gamer I was talking to. He already has the CPU and GPU. We were trying to dissect a performance problem and the dreaded 'bottleneck' term came up ;P I'm just no good at explaining things so I thought I'd jump over here and ask the pros.