Testing for stability with unlocked 4th core?

I just put together my upgrade last night, moved from an Athlon 64 X2 3800+ to an Athlon II X3 455 Rana with a Gigabyte 970 Mobo and 8GB of GSkill DDR3 1600. Just to try it out, I attempted the core unlock through the board. It seemed to work fine and recognized the proc as a Phenom II X4 B55 Propus. I switched it back shortly after, as it was very late and I didn't want it running over night before stability tests.

So my question is this, what's the best way for me to safely test the stability? Is there any real danger of "frying" anything out with the unlocked core? What should I do to verify that it's ok running that 4th core and stick with it?

Thanks for the help!