Asus Maximus Hero iX 2nd m.2 drive

[New_Ninja]

I am unable to get my computer to boot or enter bios if I add a 2nd m.2 drive. i get the error below.

[DevBiker]

You're trying to put a SATA M.2 into that socket. That won't work; it has to be a PCIe/NVME drive. On the Hero IX, you can only put a SATA M.2 into socket M.2_1.
See page 1-29 of your manual.