My Intel I7 4771 works on 3 cores instead of 4

[Youssef Walid]

My BIOS settings is set to 3 but I can't change it to 4, every time I change it to 4 it instantly goes back to 3
My mobo is Gigabyte Z87X-D3H

 

[Amdlova]

that motherboard can save photos on bios try save and show to us!

 

[Youssef Walid]

Nevermind, I resetted the voltage to auto and threads to auto and now It's running on 4 again.

 

[Amdlova]

IF you don't know what you doing in your bios, please have many posts and step-by-step to OC or other kind stuff. You can Warm your processor and Avoid the Warranty