Will a Antec KUHLER H2O 620 oc an i5 3570k to 4.5ghz with decent temps where i live right now its around 30 degrees celcuis in summer, i have a corsair 300r with stocks fans if thats help.
to 4.5 maybe but overclocking is a gamble so 4.0 - 4.5 but try your luck!