Originally Posted by /\\/uLL
Alright, well, I'd say set ACC to "Auto", Unlock CPU Core to "Enabled" then "F10" to save and quit BIOS. Go right back into BIOS upon the reboot and see if the other two cores are listed now. If it won't with ACC/UCC turned on then I suppose you could try upping the vcore to something like 1.375 and trying again. If it still won't post much less show the other two cores I'd start to think that your 550BE only has two good cores.
I think this is the case with most unlocking attempts. A lot of people try and fail, but don't report it here. A lot of people fail get another chip, fail, get another chip, then succeed, then report it here.
At least in my case, my 550BE won't do anything with ACC etc on, off, higher volts... just won't unlock. It does, however, OC lick a banshee.
I rarely use more than one core of it anyway, and it is very nice to have the second core to pull extra processing load. So 3 or 4 cores would benefit me very little, and I don't think it would OC as well with the extra cores active. Therefore in my case I'm better off with just OCing it with the current 2 working cores.
Something I did notice is that while main core runs at the standard voltage the second core runs about 0.2v hotter. So OCing and running first core at 1.45v pushes the second core to run at 1.65v.
Not sure this is such a good thing, and maybe I'm OCing my chip too much given I might have a weak second core on top of the 2 locked ones.