Yes and no. I've set it up so it turbo boosts all four cores to 5GHz if the CPU is at 90% stress or more. It normally idles at 1.6GHz and undervolted. The picture below is rather a high Vcore for 5GHz, I've toned it down to 1.37V since then.
This is my highest overclock:
Edited by Tangster - 1/20/13 at 12:22pm