AMD's Trinity APU (A10-5800K) has been overclocked to 5.1GHz with air cooling - and beyond 7.3GHz using liquid nitrogen.
According to PCGamesHardware.de, the overclockers disabled two of the A10-5800K's cores, allowing the APU to exceed speeds of 7.3GHz.
As Mark Tyson of Hexus points out, a standard AMD A10-5800K APU is equipped with four cores and runs at clock speeds of 3.8GHz - 4.2GHz as the system demands.
"[Our] own AMD A10-5800K sample was a little disappointing as it only reached 4.5GHz with air cooling before instability started to show its ugly yet all too familiar face," he explained.
"While our own overclocking required a voltage bump to 1.45V to attain 4.5GHz, the guys over at PCGamesHardware.de noted that voltages of 1.616V (air) and 1.956V (liquid nitrogen) were used to achieve their headlining overclocks."
Obviously, most PC modders are not going to be pouring liquid nitrogen on their AMD Trinity chips anytime soon, so you have to figure the 5.1GHz is a more realistic overclocking target for most tech enthusiasts.
If you do want to overclock your APU, be sure to to disable Turbo Mode in the BIOS - otherwise your results will be throttled.