I currently have a Pentium IV 530 (3.0 ghz EM64T) that I use as my main PC. I plan on running 2 computers attached to a KVM so I ordered a new board for my mac and now I need to decide what CPU to throw on it.

This is for my Mac should I

A. Use my current PIV and just get a Celeron D for my PC $50

B. Get a Pentium D 805 for the mac and use my PIV 350 on my PC $91

C. Get a Core2 Duo E6600 for the Mac and the PIV 350 for the PC $190


I'd like the core2 duo but I am not sure I want to spend the extra $100. I guess the real question is will I see much improvement on the Mac going from a PIV 350 to a Pentium D. I don't really care about the speed of the PC because a Celeron D would be just fine for what my PC is going to do.

Get the E6400 then, that's what I have, and I couldn't ask for more.

my bad I meant the E6300 not the E6600

The E6300 is still worth it dude. It's seriously worth every penny. You can overclock that bad boy well over 3ghz.
I never really liked the Pentium D's anyways. But if that's what's needed to get you into mac, I'd say go for it.