A Japan based overclocker was able to get a 96% CPU clock speed increase and 121% GPU clock speed increase during a "suicide-run" using a retail AMD A8-3870K Black Edition processor.
Then end result of 5,875 MHz is pretty amazing, done with a base clock speed of 125 MHz versus a 47.0x multiplier.
The CPU Voltage required, get this ... 1.872V :)
The integrated IGP was overclocked to 1,327 MHz from its default 600 MHz.As impressive as the clock frequencies are, the system was too unstable to run benchmarks whatsoever. The motherboard used was a ASUS F1A75-V Pro motherboard, G.Skill RipjawsZ memory and a lot of Liquid Nitrogen.