Go for the i5-2500k, for the price difference it wins in terms of performance/dollars. You can also overclock it to higher frequencies than the i5-3570k which can close the small gap of performance difference. If you do overclock to 4ghz make sure you buy a good CPU cooler, if your budget is tight I guess you can go for the Hyper 212 (almost a standard now, I think hyper 212 has appeared over a 1000 times on the forums
) or if money is not a factor go for the Noctua DH-14 as one of your coolers. The DH-14 is one of the best air coolers, there may be a few better such as a phanteks one but I just can't remember the model number. I may come back to let you know the model if it does click in my head.
- Socialfox