So I don't see if you are checking with the maker if they have a newer BIOS.
Some BIOS's are just buggy. I've had to swap motherboards in those cases, but is the BIOS the latest and if that didn't fix, what does the maker/seller have to say?
(I agree it's defective.)
Built a new Ryzen rig a few months ago.
Stupid thing will not boot to Windows when an external HDD is connected.
It attempts to (gets to the Windows splash screen for a second then the screen blanks out and prompt "Windows is loading files
" slider appears at the bottom of the screen twice... Then it opens the BIOS window.
Disconnect External drive & off it goes...
Now I have tried the following several times with no success.
1 - 3 different external HDD.
2 - Plugged drive into various USB ports.
3 - Reset BIOS to default.
4 - Made sure the internal SSD is set as first boot device.
5 - Disabled every internal device in BIOS so ONLY the SSD is seen.
5 - Disconnected EVERY internal drive (2Tb HDD & Blue Ray writer) and tried to boot with external HDD connected.
6 - As above but tried connecting SSD to various internal SATA connectors.
Regardless of what I try...
External HDD connected... No Boot.
External HDD disconnected... Boots fine.
It's only a wee issue cause I tend to keep the unit on 24/7 anyhow but the fact that it is doing it in a brand new build is driving me nuts!!! Am I missing something really obvious?

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