Download the manual of the Gigabyte board and look for an acc setting. You can set it to auto or enable it. If the board won't post, you'll have to reset the bios using the cmos jumper or remove the board battery for one minute with the power supply unplugged. If the board won't post, it means the cpu won't run with the unlocked core; I have two sempron 140 cpus; both have bad second cores that won't run unlocked. If you want four cores, then I would get a four core cpu. But honestly, most applications won't even use the three cores you already have.