Even though the Radeon 8500 is faster than the Radeon 9000, the latter is based on the Radeon 9700, that means that it supports PS v2.0a and VS v2.0 while the Radeon 8500 doesn't. And both PS and VS have to be at least v2.0 to be supported by ZeroGS. That means that probably you could run ZeroGS on a FX5200 even though that's got to be the worst video card of all times.
I have a question though, having code rewritten to use PS 3.0 should improve rendering speed, as usually PS 3.0 code is smaller than PS 2.0 code but rendering speed isn't the main bottleneck in PCSX2 right? it's the CPU and co. right? That probably is the reason why FSAA doesn't impact framerate.
Regards
Lugaidster
PS: Sorry if I mispelled something, english isn't my native language

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