Yep, I have same CPU at 4.8, its a rock and H2o cooled 28c idle and 34 under 100% load.
I had my CPU at 5.2GHz and it ran great, could game and everything, but 3Dmark would crash to desktop.. and with a i7 2600K 4.8GHz is very fast.
Thats 1Ghz faster than stock