Don't try turning on LLC...do it now and leave it on. You are supposed to be using at least a LLC of High at your clock speed, and possibly Ultra High. Ask anyone else for their opinion, they'll say the same thing. There is no reason for you to be running a .085V offset just to run 4.6 GHz. It's forcing your idle load to be almost 1.1V when it should be at or below 1.0V. And as you point out, you can barely even hit the 4.8-4.9 GHz range on an even more ridiculous offset headed into the +1V territory. You are doing it wrong.