I have a i5 3570k with a asus p8z77-v lk. I had the boost at 4.2 and it was boosting to 4.2 but after today it just stays at stock 3.8. I have tried just using the fast performance overclock setting in the bios that used to give me 4.222 something like that overclock. But today it just satys at stock. I have reset the bios and it just stays the same. Any help would be appreciated.