5 ghz on an AIO similar to the H80 is pretty impressive to me. If all chips are capable of hitting those clocks with those coolers, we can probably see 5.3+ ghz clocks on water, provided these don't hit a voltage or frequency wall.
1.452 V??? My 8120 can run at the voltage long enough to finish Cinebench one time. They must have designed a whole new architecture to keep it stable on a H80.