I recently had issues with my system and since I had no other parts to really troubleshoot everything I bought a phenom II x2 555 black edition and biostar a780L combo.
I went with the am2+ board since I still had ddr2 ram, 2x1gb crucial ballistix 800mhz
It turned out that one of my old ram sticks was dead, so I was running with only 1 one gig stick installed.
I unlocked the cores in the bios and everything went smooth, ran prime95 for a few hours with no problems.
Windows 7 ran fine, I even managed to game a little at low settings for over a month and never had a problem with the extra cores.
I installed the ram, enabled acc and kept getting a no operating system found error
I put everything to default in the bios, got into windows and tried a clean boot
It solved the missing operating system error so I tried acc again, now the system locks when windows 7 starts loading, right after the little orbs start coming out of the darkness to form the windows logo.
I tried different settings on voltage and timings for the ram and nothing helped, I upped the voltage on the cpu and still nothing
The ram will also not run stable at 1066 even with the timings loosened so I know it is going back to the store.
So my question is:
Why is the ram stopping me from unlocking the cores and what ram can I get that will allow me to do so?
Keep in mind that I had both locked cores running fine for over a month so I know that they work.
The biggest problem with unlocking your extra cores is just that. Its not guranteed by either AMD or the mobo maker. Your best bet is to go out and buy the exact same memory that you had.
Now with a cut core CPU if it is bad it could have been anything. It could have been the cores itself or the cache. It might even have been linked to the IMC not being able to handle more than the cores that were given.
If anything you might have a corrupt OS install due to faulty cores being used.
I had a kit of 800Mhz crucial ballistics. It failed 4 times, I have RMA'd the kit 3 times and finally gave up. This particular kit is notorious for failures. The longest I've had a kit work for is 8 months.
This one had pretty lights, so if you have a kit like that I'd research it.
Of course it could be just a normal failure, in which case Crucial has a lifetime warranty.
From all the posts I've read about the Phenom II X2 555, it seems that most have been able to unlock the extra cores. But, don't buy this board thinking you'll, with 100% certainty, unlock two, stable cores. A friend purchased the Phenom II X2 555 hoping to unlock. I did get two cores to unlock for him, however, when I tested them with prime95, they both started spewing out errors within two hours. Also, unlocking the cores will disable the core CPU temperature sensor. So, make sure you have good cooling and ventilation if this CPU+unlocking if you decide to do this, in your case I guess you blew it.
buy the processor you want, AMD binned your chip as a 2 core processor for a reason maybe it posted and ran for a bit but had unknown issues with the 2 bad cores or maybe they had physical defects that once power was introduced over time cause degridation or failure... or maybe its the ram, who knows.
try the ram in another machine, if it works fine grweat if not RMA
and as always buy the processor you want not the one you hope it unlocks to become