Guess you have Rev 1 and limited to 1333, download CPU-Z a free program and run it then click on the memory tab under frequency it will prob show 667 or so indicating you are running 1333. The overclock failed message is telling you it didn't take the OC you tried to 1600. For temp checking, suggest downloading an app called CoreTemp - also free, it's one of the better little apps I've seen and uses low resources/overhead