At that point you would be playing with either hardware or firmware. Modifiying OS behaivior alone won't do it.
Depending on the model there might be some room for boosting TDP or frequency response curve, but the maximum multipler is definitely locked.
There was a microcode bug that allowed 4**0MQ/HQ laptop CPUs to be multiplier unlocked. We can dream about the same thing happening on Xeon E5's. Really high clocks on all cores still won't happen though. We'll run into power/thermal limitations. (Imagine trying to handle two 6950X in one socket.)
Edited by MrKoala - 6/27/16 at 2:13am