No GPUs found when using a riser card.

[nueverest]

I have two Nvidia 1050's. One is plugged directly into the pci-e x16 port on the motherboard. The other one is plugged into a pci-e x1 slot via a riser card.

OS: Ubuntu 16.04
Claymore v9.6

When I run claymore I get a GPU invalid index error, and neither card is detected.

When I disconnect the riser card and boot up again the single card setup does work.

Any thoughts on how to get this riser card to work?

[dlethe]

Take Linux out of the equation. Take the riser out. Test the BIOS sees one of them. Swap the cards. Does BIOS see that one. Put riser in try all 4 combinations to determine if it is hardware or software

[dlethe]

The key is to trust nothing. Maybe the pci slot has some bad lanes. Maybe the riser you bought is bad, incompatible or you didn't give it power, or your power supply can't handle it. Also just try one card and put that in the riser. If it doesn't work in BIOS then you know it must be the riser

[nueverest]

The BIOS seems a bit antiquated.

1 Card attached via a riser does work, but when I attach more than one riser it no longer works.

I am going to try getting a large power supply to see if that is the issue. The power supply actually doesn't have a power rating written on it.

The exact error message is:

cuda GetDeviceCount returned error 10
Invalid Device Ordinal
No NVIDIA CUDA GPUs detected
No AMD OPENCL or NVIDIA CUDA GPUs found, Exit

[entity279]

You are of course aware that you may need to short the 'presence' pins of PCI-e slots when using risers?

[nueverest]

I was not aware of this. Where could I find more info on 'presence' pins?

…

On Tue, Jul 11, 2017 at 6:56 AM, entity279 ***@***.***> wrote: You are of course aware that you may need to short the 'presence' pins of PCI-e slots when using risers? — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#48 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ACyD-gLPKf3ABt2hd8xiOGB5SV50DTEqks5sM38IgaJpZM4OTn8r> .

-- Chad Nelson 480-659-2787

[dlethe]

That depends on the riser. I didn't have to do anything with mine. But they are powered risers. Everything I read has said to use powered risers and you won't have problems.

[entity279]

http://blog.zorinaq.com/whitepixel-breaks-286-billion-passwordsec/

Search for : Shorting Pins for "Presence Detection"

I also disagree with the comment above, in case it was stating that powered risers allow you to get away without shorting presence detection. This was definetly false in the tests I've done

[nueverest]

After speaking with ASUS technical support, it turns out that I needed to go into BIOS

• Boot -> Enable 4G Decoding.
• PCH -> PCIe -> Gen2

This allowed me to use up to 5 riser cards. There are still 3 more slots on the board, but 5 is better than 3 so far.

Motherboard: ASUS Z270 Mark 2

[twangnh]

@nueverest I tried your setting, but still cannot detect the GPU connected with riser, other 3 GPU directly plugged in the motherboard are detected.

[fabiogatti]