I've had a Gigabyte Z170X gaming g1 mobo in my system.for 2-3 years now. I have no complaints it's a great piece of hardware. I decided about 1 year ago that I wanted to try the gigabyte software (app center, easytune and SIV) I installed them and they worked as intended. I decided to be adventurous so in the easytune app I overclocked my I7 6700k to 4200. It overclocked super easily. After a few days at 4200 I decided I wanted to return to the stock speed of 4000. Low and behold! Suddenly easytune no longer works. When I clicked on easytune it would not open. Could not get SIV to open either. Whenever I click on one of them, a message pops up easytune engine restarting and no matter how long I wait, it never works. I've even tried completely uninstalling all gigabyte apps but the OC remains. Even cleared CMOS and restored system defaults in uefi and still the oc remains. Went into advanced windows power settings and adjusted min and Max down to 80% but still the OC remains. I'm on windows 8.1 64 bit. Thank you guys!