A while ago Asrock announced it was possible to overclock non-K model processors with the help of a BIOS upgrade. In a short time they released such BIOSes for a multitude of motherboards and then send out all kinds of marketing materials and press-releases. 

As it seems, ASRock silently removed these BIOSes and that functionality. They even called and marketed this as SKY OC. SKY OC was is obtainable simply by a BIOS upgrade from ASRock’s official website. Even the press-releases have been removed from their website.

The BIOS disables the on-board Intel graphics and also CPU Turbo Ratio and C-State would be disabled. After that some very interesting findings would be happening with BCLK overclocking. Likely Intel had a say in the removal and support of ASRock SKU OC as users could get more performance with a cheaper model CPU. Some overclockers even reached 4955MHz with a simple Core i3-6320.

No more SKY OC for the ASRock Z170 Gaming K6+

The other manufacturers still carry support for this feature, MSI, Biostar, Asus and Gigabyte all have a similar option availble in their BIOS.