I have a very similar problem with my P8P67 pro.
After clearing CMOS and popping out battery on board:
It does the double boot issue most people have on a cold start, on 2nd boot it boots to bios, press F1 to set settings.
Even if I don't change anything, on Save and Reset from BIOS it will attempt to reboot and fail. Manually power back on and get Overclocking Failed message, press F1 to enter BIOS. I'm able to boot into Windows. If I try to restart in windows it will try to restart, fail, and shutdown (red LED for cpu is the last post it makes). Powering back on brings Overclocked failed message F1 to enter BIOS.
Pretty much if I touch anything in the BIOS it's a 50/50 chance I get Overclocked failed and can direct boot into windows via the boot menu OR depending on what values changed in the BIOS it won't boot up at all and I have to reset CMOS.
My 1.6v 1600 GSkill Ripjaw X CAS 7, 7-8-7 ram is running at 1.5v 1300, CAS 9, 9-9-9.
CPU temps are around 27C in Windows @ idle around 32-34C in BIOS.
I tried remounting the motherboard making sure all the standoffs were tight and in place, unplugging everything, booting with 1 stick of RAM. Only thing I didn't try yet is remounting the cooler, because it's massive and the Noctua NH-D14 is a pain to install.
Tried 1053 beta bios and 1003 stable bios same thing.
On the plus side, besides my RAM running slower than it should and 0 potential for overclock until this is fixed, my PC runs rock solid in Windows.
2x4gb Gskill Ripjaw X
noctua NH-D14 cooler
60gb SSD for windows