Asrock z170 gaming k6 Dr debug errors

Samsung ssd 870 evo. Logitech mouse and keyboard. Zotac 980ti amp extreme. That is all.

I unplugged everything from the mobo (step by step, testing every time) It's just the ram, the cpu, the heatsink and the hdmi monitor. Not even a video card or hard drivers or any usb are connected, so that is not the problem. And the bios is I think 1.90, or anyway, the last stable one, I checked it two days ago, and it was still up to date.
The psu is a new evga 750 g2, which does not seem to be the problem. It's one moth old, just like the mobo.

Edited by Filoppi - 21 Jan 2016 at 7:25am

Last night I got a blue screen on my asrock z170 gaming k6 (not the first one, but I think the other ones had different reasons, and they stopped anyway) on win 8.1 while doing some average work, with something like IRQL NOT LESS OR EQUAL, I restarted, and got two other bluescreens before windows could finish loading: thread expection not handled. So I went into the uefi bios and disabled every c state and cpu slight overclock, I restarted, and before the pc could output any video, it started giving Dr debug codes, I'm getting a few different one (apparently randomly) : d0, 5d, 62, 79, 00, 19, 04, 40. I tried removing the mobo battery and resetting the cmos hundred times, removing the ram and moving it in every possible combination, removing the vga and switching to the second bios... Nothing fixed it, I'm still getting the same errors. It looks like the mobo is broken to me, but I don't want to rma it for nothing.
Do you have any ideas?
Thanks.

Edited by Filoppi - 21 Jan 2016 at 7:32am