With a hyper212, your best OC will be @4.2-4.4GHz depending on the cpu. You should be somewhere around 1.108v-1.216v which is lower than default auto voltage, but temps will be higher because of clock speeds. You could push higher clocks, but you'll start to see less gain from speed vrs temps going up as that cooler starts topping out in ability.
For just cs:go and other games like it, the 3570k is better than the i7-3770, just on clock speeds ability to push higher IPC. However, in overall ability, if you branch out to other games like WoW or gta5 or the Battlefield series, the multiple threads afforded the i7 will show better results.