Games don't really heat up the cpu to the same degree as stress-tests like prime95 and IBT and AIDA64. I wouldn't be too worried with a 4570 on the stock cooler. BUT, if I planned to use the thing for more than 3 years then yeah, I'd buy a $35 cooler and sleep better at night (but if I planned to use it more than 3-4 years I'd also buy an overclockable cpu). Intel's coolers are self-described as being "adequate to cool the cpu through the warranty period". From my experience with a i5-4670k Haswell, the stock cooler is good enough to keep the chip "cool enough" in regular not-overclocked situations but has toasty mid to high 70s temps on not-overclocked stress-test (p95, IBT, AIDA) runs. If you are looking toward the long-term, then a reasonable $35ish cooler is a good investment.