an issue on the second PCI-E slot of mobo

[Wally Lee]

I have 2 gtx 1060 but they're from different brand (MSI and Gigabyte). Both of them work fine when I plug them in the first PCI-E slot on my mobo (the x16 one). However the second PCI-E slot does not recognize any of them. I aware that the second slot is dead so I tried to install a
PCI-E usb card into that slot and it works. So I don't know why it does not recognize the second GPU. I didn't forget to plug in the power cable for the GPU, I use dedicated power cable for each GPU.

Did anyone encounter the similar problem? Do I have to modify drivers/Bios to let it recognize the second GPU?

My PC specs:
Mobo: Gigabyte Z97 Gaming 3
PSU: EVGA 850W
GPU: nvidia gtx 1060
RAM: Gskills Ripjaws 2x 8GB
CPU: intel 4570

 

[mdd1963]

Is there potentially a BIOS option for setting/changing PCI-e lanes configuration of X16 vs. x8/X8 config?

 

[mdd1963]

If auto won't work, try setting each of the two being used to X8? (Hopefully system will not mistakenly interpret this as being an SLI attempt)

 

[Wally Lee]

If auto won't work, try setting each of the two being used to X8? (Hopefully system will not mistakenly interpret this as being an SLI attempt)

I tried to look around for that setting but haven't found it. Not sure if it's there. As in the
manual it seems that the mobo will auto switch to x8/x8 when it detect another graphic card in the second slot.