With Intel right now, you may want to go with the Intel Pentium 4 LGA775 sockets so a 3.2Ghz, should do. Along with that, I'd suggest the
Asus P5GD1 - a good PCI-Express included motherboard.
About your ATI vs. nVidia question - it's much the same as Intel vs. AMD - boils down to self preference. It also comes down to budget - how much are you willing to spend?
kram
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