Actually Uncfan, Loneninja was correct. The 7750 is a Kuma dual core which was nothing more than an Agena phenom with 2 disabled cores. There are 2 more cores on that die. At the time, AMD was still producing the last of the Brisbane X2 chips. Those were the native dualies. Native Phenom based dual core chips didn't come around until after the 45nm die shrink.
As for unlocking, I have not heard of it being done on the Agena chips at all. That may be due to the fact that AMD had lower yields and a larger percentage of the disable cores were actually defective. It could be it just didn't work on the Agenas, or perhaps fewer people had ACC available since the SB 750 was released fairly late in the Agena cores lifecycle and the 710 even later.
Give it a whirl. See what happens and let us know.