Overclocking FX-8320 4.3GHz @ 1.4v (mostly stable) PC will turn on, then off for a few seconds, then

[Cjmax]

I have my new processor (FX-8320) overclocked at 4.3GHz and 1.4v stable while booted into Windows. Running Prime95 I encounter no issues after I have been booted up, CPU-Z reads 1.36v and not 1.4v, but other than that I don't see any issues regarding performance or statistics from the processor. With a NZXT Havik 140 and the FX-8320 at 100% load on all cores, I am getting a maximum temperature of 52c. Well below the 55c at stock speeds (3.5 to 4.0 turbo) with a stock cooler. The system runs flawlessly while playing games, running normal things in windows, multitasking, etc. but any overclock on the processor will cause a weird boot symptom. When I press the power button, instead of regularly turning on and jumping into Windows, it will turn on (lights flash on) and quickly turn off. Fans will stop spinning, lights off and everything for approximately 3-5 seconds. Then, it will start like normal without any interruptions or faults from then on. This only happens when there is an overclock applied to the processor. Otherwise, the system boots and posts as normal. Anyone got an idea as to what setting might be causing this?

Processor: AMD FX-8320 (4.319GHz, 1.4v BIOS setting, Performance boost off)
Motherboard: Gigabyte GA-990FXA-UD3
Power Supply: OCZ ModXStream Pro 700w

Any ideas? Thanks in advance!

[darkride196]

This could be a psu problem, or even a bios issue, try switching your 4 pin cpu cable to the other one. Try reseting your bios as well.

[Cjmax]

It is most definitely an issue with the BIOS. This only happens when tweaking the CPU frequency setting when overclocking. On default settings or default w/ over clocked RAM the issue doesn't occur. I can't switch where the processor power cable goes because my board only has one 8 pin CPU power plug. I am led away from the idea that it might be a PSU issue because the system hasn't shown any signs of instability with both GPU and CPU stress tests running for hours or when gaming. This doesn't completely render the PSU innocent though.

Any other ideas?