@car1999

OK, I made a weak try to get 9 GPUs running in Win7 (using 2 M.2 to PCIe converters on ASUS Prime Z270A) and it didn't work, but the method I tried wouldn't have gotten 8 to work, so I'll probably need to revisit a little more to be sure.

I then moved one of the M.2 converters to the MSI Z170A Gaming M5 to get an 8th GPU there, but the BIOS wouldn't recognize anything on either of the M.2 slots.  I suppose the converter could be bad since it didn't work in either system.

Anything special you needed to do to get the M.2 to PCIe converter to work on the Gaming M5?  What BIOS version are you using and what are your BIOS settings for PCI and monitor?