Fine. It's basically power-on-demand, energy-saver otherwise. BIOS default is Enabled unless you turn it off. I noticed you OC - some people who do that like to keep it disabled to run at the full-speed OC all the time. Never understood that; yeah, if your gaming or doing a lot of CPU-intensive things then you want the speed, but in those situations, SpeedStep has already kicked in and your CPU is running at it's top speed anyway.