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Originally Posted by mike752
As some of you may remember, my 550 wouldn't unlock at all (wouldn't even get to the POST beep; it would just turn off five seconds after the power button was pressed). I decided to give it another go today, since I was cleaning the insides of the PC and everything was open, so I could reset the CMOS if needed.
So I unlocked it, and I actually heard the POST beep! However, it got to the point where it displayed the CPU name "AMD Phenom II x4 B50," but then it would reboot and reset the ACC setting itself, making it a 550 again.
I tried increasing the CPU voltage all the way to 1.55v. Should I also try the NB voltage? Anything else I should try?
If you haven't tried already, update your BIOS to the latest version. Afterwards, unplug your power supply from the wall and reset your CMOS by shorting the jumper leads and removing the CMOS battery. Wait a minute.
Plug the power supply back in again, and go into BIOS. Load default settings and reboot.
Afterwards, go into BIOS and change EC firmware to Hybrid, and ACC to auto. Reboot.
Any X4 designation? If not, your locked cores are defective. You can try the voltage increases as stated in the OP. I know you want to try 1.55v, but more voltage doesn't necessarily mean it will unlock.