In my case, it was sorted by adjusting NB et RAM voltages. I no longer have those issues now.
Interestingly, I found a way to trigger that boot hang up when my OC is unstable. If I decrease NB or RAM volts, when I try to enter the bios, it hangs up, a reset is needed, than I can boot without even an OC error message sometimes. As soon as I adjust NB and RAM voltages, I'm again rock stable at boot/bios load.
Guess, every system has its specificsThe most important to consider, is that it's hard to 100% be sure ofan OC, it needs time...
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