MSI Z170A Gaming MB only recognizing 5 of 8 NVidia 1050 GPU's

I have flashed the BIOS with the latest update from the MSI website and went into settings and made these changes:

PEG 0 and PEG 1 set to Gen1
Above 4G Decoding set to Enabled

I am running Ubuntu 16.04

On the MSI Z170A there are:
3 x PCIe 3.0 x16 (dual: x8 mode; triple: x8, x8, x4 or x8, x8, x1 modes; single card: x16 mode)
4 x PCIe 3.0 x1
and I added a PCI extender for the 8th card as described at

Also tried to install Fake Monitors from some code I found online:
[u]!/usr/bin/env bash

Generate an xorg.conf with faked monitors (for each of your cards)

You need to run this everytime you add or remove cards.

sudo nvidia-xconfig -a --allow-empty-initial-configuration --cool-bits=31 --use-display-device=“DFP-0” --connected-monitor=“DFP-0”

echo “Done”

Nothing has had more than 5 of the 8 GPU’s recognized. Any advice would be appreciated.

It’s probably just a limit of the SBIOS.

You can follow the method here:

to discover if the system BIOS is properly allocating all the resources (BAR ranges) necessary for each GPU to work and be properly used by the driver.

I don’t really know how you are using a x1 slot to support a GPU, those usually have different mechanicals. Even if you get the x1 slots to work, your GPU performance on those may be dismal.

If this going to be used as an Ethereum mining rig, the PCIe bandwidth may not matter much. I am wondering how one can get a GPU to work on a PCIe x1 slot, though …

Thanks, I’ll give it a try when I get home. I am brand new to all of this, totally clueless, and probably lucky it is working at all. Yes Ether, I’ll post a link to the pic of what I am calling a PCI extender when I get home it came in a bundle I ordered.

Here is link to where it/they (there’s two slot’s on the board)plugs in.

Are these extenders basically simple unshielded cables? I don’t have practical experience with PCIe extenders but I take a dim view of such gadgets, as it is not difficult to imagine issues like crosstalk, impedance mismatch, susceptability to EMI, all potential sources of poor signal quality. I am also wondering how the power supply for all these GPUs is set up.

Ax txbob pointed out, your issue may be caused by limitations in the system BIOS, rather than any physical (electrical) issues.

You might want to run some experiments to determine which three GPUs in particular are not being recognized. The results may hint at the reasons for the inoperability of these GPUs in your system.

Yes, I think it is something with the BIOS, but I can’t even really tell you what a BIOS is. Like I say I switched PEG0 and PEG1 to Gen 1 and enabled 4G, and also tried flashing a couple different BIOS from the MSI website but no luck. If I did not make the changes listed above it only recognized 4 GPU’s.

Here is what the part looks like…I have a dim view of the Bundle I bought right now.

Is there a way to make the MB think there are 8 monitors hooked up?

Sorry to say, those PCIe extenders don’t look very confidence-inspiring to me. Are you at least supplying sufficient power to them?

Anyhow, it is entire possible that this motherboard is simply not designed to operate with more than four or five GPUs, no matter which system BIOS version is installed.

This forum is probably not the best place to ask about how to get such a system to work. I think you are more likely to find people with relevant insights into such a homebrew system on forums that specialize in that kind of thing, or may be even on forums dedicated to Ethereum mining.

They are all independently powered directly from a 1250W power supply, then connected to the MB VIA the Risers Molex & USB and I am getting right at 12 MH/s is that good for 1050’s?

I would be happy to get the 7 working and tinker with the x1 after that but I think if 7 work 8 will too.

These MB’s do work with 8 GPU’s or so the seller claims, but the seller uses EthOS and EthOS does not support NVIDIA so that is why I thought I would try here. I did find an VLOG online of someone who had 7 GPU’s working this MB and that is where I found the code:

[u]!/usr/bin/env bash

Generate an xorg.conf with faked monitors (for each of your cards)

You need to run this everytime you add or remove cards.

sudo nvidia-xconfig -a --allow-empty-initial-configuration --cool-bits=31 --use-display-device=“DFP-0” --connected-monitor=“DFP-0”

echo “Done”

@txbob - I read the link you posted but I’m not experienced enough to make heads or tails of it, but thank you for the input.

I know nothing about the Ethereum world, other than that it exists. I have been ignoring all crypto coin crazes of the past 4-5 years. So I can’t comment on whether your hash performance is where it should be.

I live in California, where we had the Gold Rush starting in 1849. The people who got rich during that time were, with few exceptions, the people who provided lodging, food, and equipment to the miners. One of these rich tycoons was Leland Standford, after whose son Stanford University is named. Personally I think there is a lesson to be learned from history.