Asus H170-Plus D3 unlock BCLK

Is it possible? Looks like on earlier BIOS it was. Want to overclock my 6400T.

I believe you need BIOS 903 (H170-PLUS-D3-ASUS-0903.zip) if you can find it, it was removed from the Asus web site.

Some guy reported bricked board by downgrading BIOS, so looks like only some modification need.

Asus motherboards tend to have lock in place to prevent downgrading, read this thread.