If you run an X800Pro on an 2.4c, you're not doing the video card any justice. I'd say the video card would be limited by your CPU.
To go with the A64 setup, you have to get new Mobo+CPU+Ram I don't think you could use the PC2700 with it. At least I wouldn't (Want to)...
So if you decided to go with the A64, what would you do about that 9500Pro? Still run that same video card? Then you'd be choaked at the video card level and not the CPU level.
I'd go for a more balanced upgrade. Maybe keep your current mobo and get a faster CPU, say 3GHz and a 9800Pro video card. That'd probably perform double what you currently are ruuning.
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