Most OEM motherboard do not have options for unlocking extra cores on processors. A Sempron 140 will unlock to a dual core it was set up that way because it did not pass certain tests after unlocking. So, one of three things can happen when you try to unlock the second core. 1) It will unlock successfully and work as a dual core processor. 2) The second core may cause your PC to become unstable. 3) It may not be possible to unlock the core due to so many defects with the 2nd core.