Basic Questions
 

So I'm in the market for a new computer, mine is just way too outdated to do anything with. I'm also a cheap, ignorant bastard so I have a couple questions to field for y'all. Before all of that though, I will NOT be "upgrading" to Vista, I'll be keeping my XP Pro, so dx10 is of no concern to me.

Is there a huge difference between the nvidia 8400GS, 8500GT, and 8600GT if they're all 512MB?

I've heard that AMD is having problems with their dual core processors. Is Intel the way to go now?

Is there really that big of a difference between the 1.8 Dual Core and the 2.0?

Thanks for your time.

*EDIT* What is a good PSU for those cards? Will 350 or 400 do?

There's been a few threads here recently on this very subject. Even browsing the first 10 topics would yield a great deal of information.