Firstly F33LTH3F0RC3, Why AMD, Intel are clearly owning the market at the moment with their Core 2 CPUs, they far surpass most/all of AMDS offerings at the moment.
Secondly, For heavy gaming, Id say absolute minimum of 2GB of ram but id stroingly suggest 3-4gb, its so cheap its a silly to end up with main memory as a bottleneck. Also, ensure its DDR2 or 3, preferably DDR3 if you are building a new system.
For GP4, the more powerful graphics card you have the more AA and AF you will be able to get away with, resulting in a sharper and crisper image. However as someone else mentioned, GP4 is quite CPU bound, and a fast Processor with a nice amount of L2 cache will run GP4 a treat (Fast CPUs allow you to run hi-poly cars, lod 0 only etc, it also helps dramatically with the hi-res textures).
There's just a few pointers, if you need any more help, or would like some help spec-ing a system up for a given budget, i'd be happy to give you a hand
.
__________________________
Help keep our forums tidy.
Use the search function...