This item allows you to select the CPU performance state during system boot before the OS takes control. The CPU runs at a selected performance ratio based on CPU config.
I left it at Max Non Turbo Performance.
I notice there really not that much to gain with OC, looks like the CPU jumps up to 3.8ghz with a load on it. I been out of touch with the newer stuff but looks like you get a lot more bang for less power with these CPU's of today. Next will be upgrading my video from a GT240..maybe I don't play any games so that card may still be plenty good.