disappearing M.2 drive

[mauricev]

ASUS Prime x399-a with a Threadripper 2950x and 128 GB of 2666 RAM. NVMe M.2 boot drive and 2 TB SATA SSD for data.

With an untouched BIOS, everything boots up fine. Windows installs and runs just fine.

Either set the tuner to DOCP or the memory popup menu to Profile #1 (why does it have such a generic name?), reboot and it boots back into the bios. This happened a few times until I noticed that m.2 drive has gone MIA in the BIOS.

Reset it to the defaults and M.2 drive reappears and everything is as it was.

So it seems that altering the memory profile makes the M.2 drive disappear. What's causing this?

 

[mda]

Not sure, but the first thing I'd try is to give the memory more volts.1.36-1.4V, maybe just to see if the issue goes away?

 

[drescherjm]

I had a disappearing WDC Black G1 drive on X470 but I don't think it was memory related. I replaced it with a samsung 970 and all is well.

 

[Azrak]

I would not expect this in an Asus board, but is the DOCP profile applying some sort of BCLK overclock or change in PCIe BUS speeds? Exceeding the default 100 MHz speed can cause PCIe devices to fall off the BUS.