Multiple cores Disbaled

[ChemicalAnalysis]

I am having an issue with my CPU. My Bios, Msconfig, and device manager reports all 4 cores  and hyper threading are enabled. On the other side task manager, CPU-z, Asus's Ai Suite all report 2 cores enabled and 4 threads. I tried rolling back my bios and restoring settings but that didn't work. Has anybody seen this before. I am almost tempted to re-install windows. 

• i7 3770k @3.5GHz
• Asus Sabertooth Z77
• G. Skill Ares 2 x 8 gb 1855MHz
• 1TB WD Caviar Black
• Cooler Master 800W 80+ gold
• Windows 7 x64
• Bios 2104

[SImoHayha]

Go into your bios and change the C6 State to off and see if that helps

[Godlygamer23]

Check to make sure the extra cores are enabled.

[ChemicalAnalysis]

Go into your bios and change the C6 State to off and see if that helps

 I did and it did not fix the issue.

 

So here is what I did, I turned off hyper threading and started from 1 core to 4 checking to see if i had an issue with any cores. I found that every thing was reported correctly by task manager and CPU-z all 4 cores are running. Then i enabled hyper threading at 4 cores and the problem persisted. with hyper threading enabled i jumped down to 3 cores. now it reports 2 cores at 4 threads exactly like having 4 cores and hyper threading enabled.