The software can be good for a quick test or tune, then if it works, then apply in the bios.
EG. I'm trying to OC to 4.5GHZ, I start up prime and it fails in a few seconds. It might need a bit more voltage, so I startup Asus AI, add a bit more voltage, start up prime again. IT's stable, so then I'll reboot and apply that voltage to the BIOS. You should look up a guide for your CPU/Motherboard though and set a good starting overclock in the BIOS and go from there so you have a baseline. With my chip, it can handle 4.2ghz without any other tweaking other than the multiplier, so I'll set it at 4.2ghz, turn on and off the basic things needed from overclocking and then go from there.