+1 for the 2500K for that budget. if you were thinking of grabbing some expensive SSD or GPU resulting in you choosing a mediocre CPU instead for a compromise, i recommend you re-consider that idea.
if you're a fan of AMD, the Phenom II 955BE/965BE/960T is as good as it gets for gaming for the right price.
if you don't OC at all, and would like an intel, there's the cheaper alternatives; i5 2300/2400/3450. even an i3 or SB Pentium G840/850 is a decent option.