The selling point of CL2 is that it's supposed to run faster at 133 than CL3 at 150. AFA CL2 at 150, it depends on your RAM, but if you are running an unlocked processor at max vDIMM and vcore and can't even run CL2 at 150, then you may have an issue. Some top brands are supposed to run at CL2/160MHz and above but some just don't even at high voltage loads.