SB = South bridge. Its a chip on the motherboard. All AMD SBs from the 750 up have ACC. This is what unlocks cores. So yes. You need ACC, which is found on the 750 and newer SBs.
A while ago I asked somethin' similar, but these guys said that there were a few other things that unlock cores. I have a AMD Athlon II X3 440 @ 3.3ghz. =D