Unlock 2 cpu's and possibly OC



New Member
I have a Phenom II X2 550 3.1 and an Athlon II X3 435 2.9 still in the box and want to try unlocking one. Obviously the Phenom would be best as it has L3 but I won't know until I try if either chip will run stable w/4 cores. Some older mobo's that will unlock these, if the bios is right, can't be found.

Can anyone recommend boards that have that ACC option so I can try to unlock, and where to source them? I also will be trying to OC in the future so if any boards are better for that I'd appreciate any info anyone may care to give.




Active Member
Can't help much here, but I successfully unlocked the 4th core on an Athlon II X3 with a Gigabyte GA-MA785GM-US2H in a build I did for a coworker.

From what I remember, most AM2+/AM3 boards with a 7xx/8xx chipset from at least ASUS, Gigabyte and MSI supported ACC in the BIOS.
At least, all 785G boards I used (MSI 785GM-E65, ASUS M4A785TD-M Evo and the aforementioned Gigabyte) supported it.

Here's the forum thread I used when I did my unlock. Sadly, it does not seem to have a motherboard list anymore :( As for motherboard availability, Newegg has only low end AM3 models in stock, so your best bet might be eBay or local sellers.


Procrastinating Member
From equinoxe3d's link:

In general, make sure the motherboard has a SB710 or SB750 southbridge and ACC is supported before purchasing. However, there are exceptions, as some motherboard manufacturers have disabled ACC core unlocking features.
My aging memory tells me the SB760 also had ACC, and a bit of searching found a Gigabyte board with an SB710 chipset and an SB760G southbridge that had ACC. So bearing in mind the caveat above that some boards may have it disabled, that gives you at least three southbridge models you can search for.


Procrastinating Member
Here is another link with some info. It's outdated and missing the SB760, but in the section on ACC mentions the Nvidia chipset that has a similar feature.