Hi All
Yes, I confirm - bios need to have following description: "Add CPU core control option".
After I checked the website, so far, bios'es for MA770T-UD3, MA770T-UD3P, MA785GT-UD3H, MA785GMT-UD2H/US2H, MA790X-UD4P & MA790FXT-UD5P support this.
And you can enable these cores not only in BIOS but also under EasyTune 6 (ET6) software:
Tuner -> Advanced -> Core Boost : Enabled, then the system will reboot for updating BIOS of EC firmware and will be ready for unleash the hidden CPU cores.
Now you will be able to enable Core 2 and / or Core 3 under ET6