Intel i5-3570K Overclock with Asus P8Z77-V LX

Hi, recently I have built my new computer - parts listed below - and after everything was set up I decided to overclock my CPU using AI Suite and use the auto tune feature to overclock to 4.1GHz but sometimes after looking at AI Suite and I also check it with Core Temp. the GHz tends to change to roughly 1.6GHz then eventually return but this a consistent issue, could somebody please help me with my problem; it's really starting to bug me. Thanks alot :):)

PC:
Intel i5-3570k
Asus P8Z77-V LX
Corsair 8GB XMS3 1600MHz RAM
Asus Radeon HD 7870
WD Caviar Blue 1TB HDD
Corsair Carbide 300R Windowed case
Hyper 212 Evo Heatsink
Corsair CX750 PSU
LG Optical Drive
Windows 7 SP1

Its just the turbo state, nothing to worry about. If you want your rig to be at 4.1 all the time even when playing minesweeper then disable the feature in the BIOS. 

There is some sort of setting in the bios to do with cpu power management you need to disable that. I have the p8z77-v-lk and was running prime 95 and it would only run at 1.6 till i disabled it.

Thanks for the help :)

Will look in the BIOS, Thanks :)