MSI Z170-a PRO and usb PCI-E risers!!!

[oinquer]

I have a rig with an AMD 7970 and an AMD 7950.
Both work in any PCI-E with the old flat clable risers, but if i try to use PCI-E usb 3.0 risers they don't boot unless i'm using the PCI-E 16X slots (just detected VGA will try to install drivers today).
both cables have presence pins shorted, tried in bios to change to PCI-e GEN 1, 2, 3, auto.

ALSO, i Noticed the pin A13 and Pin A14 is direct in flat cable and crossed on usb riser.
This is a REFCLK+ / REFCLK- Reference Clock Differential pair ....from my limited knowledge this is not OK, this lines are not switchable normally....but it might work depending the protocol.

Anyone know something about it? is it the board or the usb riser?


Sorry, can someone move this to alternate coins ? as no one mines bitcoin with GPU these days...

[1714976448]

1714976448

[1714976448]

1714976448

[SpaceBallsOne]

I have an Asrock Z170 pro4, same problem.  16x slots work fine, 1x slots corrupt the screen at bios if when it boots to windows hard locks.  I tried latest bios update, tried different usb risers