[damien c]

The main difference between the I7 2500 and 2600 is that the 2600 run's a little faster at stock speed I think, but also it has more cache and hyperthreading so windows will think you have 8 cores rather than 4.

Graphic's is a sticky issue Nvidia do generally perform better but they do use more electric and cost more, but if you want to max out games then you will need the ATI 6970 or the Nvidia GTX 580.

The 580 is the best performing single gpu on the market but it is outperformed by the dual gpu cards such as the ATI 6990 and the Nvidia GTX 590.

If you decide to overclock the cpu the 2500K and 2600K models are the ones to get and they will overclock to 4.8ghz without a issue 99% of the time, with a good motherboard and cooling.