ASRock Z97x 6 gpu issue

About at my wit’s end trying to get my 6th gpu to run on the ASRock Z97x motherboard. Everything works just fine with 5, even when I install the 6th. I just can’t seem to get it to recognize the 6th for some reason. Only once so far have I gotten the UEFI to recognize something was plugged in.

I’ve checked the riser by removing another and replacing it, works just fine. Not the card, did same style of test. Have more than enough power with two psu’s…

Ran a few Google searches, only found one other person having issues but nothing else.

So I set the PCI slot to Gen 2 and got it to show up a few times both in UEFI and in the Device Manager. From there, Claymore refused to even acknowledge that I had any GPU’s installed. I did a complete wipe of installed drivers and reinstalled them all. That did take care of the Claymore issue.

Here’s where it gets weird. During the restarts for the drivers, I noticed that sometimes all 6 GPU’s weren’t getting recognized. After everything was installed, I decided to investigate. I booted to the UEFI ten times in a row, each time checking to see which PCI slots were registering. 4 times all 6 appeared. 2 times both PCI 6 and PCI 4 didn’t register. 4 times only PCI 6 didn’t register. I then switched the PCI 6 to Gen 1 and haven’t had a problem since (granted, I’ve only restarted 4 times and called it good for the evening as I’m tired and frustrated. Figure all 6 are running stable, temps are low, smoke detector tested hanging above it…good enough for tonight haha)

The only thing I can come up with is that I don’t think the mobo is getting enough power for all of the PCI slots. There were times when I was booting it up that it seemed to hang before even the UEFI screen came up. I don’t think it’s due to the PSUs so much as it is the board itself doesn’t have the solid capability to run 6 GPUs.