You have gotten many good advice NJ5, but the single most important thing in my opinion when buying a new system is to answer this question:
- how many years will I keep this CPU until the next CPU upgrade (or even a completely new system)?
(and this in relation to possible GPU upgrades too to some extent)
Personally I aim for 3 year cycles on the CPU and 1.5 year cycles on GPU, while some people may prefer for example 2 year CPU/2 year GPU cycles or any other combination for that matter. Partly I choose my strategy because I find it irritating to have to upgrade motherboard and RAM together with the CPU, but then it's a good strategy because of better-bang-for-your-buck too.
Oh, and please buy AMD and not Intel.
(not because they're better but because I love AMD lol)