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

oinqueroinquer Member Posts: 3
Hello everyone,

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.
both cables have presence pins shorted, tried in bios to change to PCI-e GEN 1, 2, 3, auto.

Anyone know something about it? is it the board? looks like im going to have to check what's the difference from flat cable and usb.


  • oinqueroinquer Member Posts: 3
    Update in case someone is able to help,
    Checking my flat cable rise and my usb riser.

    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.
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