How do I fold with Two GPUs in One box under Windows 11?

[appepi]

Could not find an existing post on this topic, so ... The general question is in the title, but my specific query is about using the two PCIe3 (x16) slots in HP Z4G4 Xeon-based workstations. Lately I bought two of these on eBay since none of my existing mothball flotilla of 1st and 3rd generation Z-series workstations were acceptable to W11, though they all run W10 or Ubuntu quite happily. I figured it would be as well to retain a foothold in Windows world in case ongoing use of W10 exceeds my pain threshold after 14 October 2025.

The Z4G4s came with NVIDIA P1000 GPUs, which are 47W GPUs roughly equivalent to a GTX 1050 in Folding performance. Once the new boxes had been settled by a few days of 24/7 folding on both CPU (Xeon W-2133, 6C 12 Logical CPUs) and the P1000, I installed the optional front cooling fans so that the Z4G4s would let me use some of their AUX power. One has a 1000W PSU with 4x 6+2-pin 12V AUX supplies, rated at 18A each, ie 4x 216W. The other has a 750W PSU with 2x 6-pin AUX supplies with the same rating. The Z4G4 will refuse to run if you try to use AUX power without a front cooling fan.

With that sorted, I moved a GTX1080 from Z803, where it runs well enough on PCIe2 (x16), but has expensive "overhead" because my Z800s tend to be supporting lots of RAM and Disks, so they still burn quite a lot of power even on idle, while the Z440s idle cheaply and I assume that the Z4G4s would also. Rather than swapping out the P1000, I left it in place and installed the 1080 in the second PCIe3 (x16) slot. I run 7.6.21 for reasons given in other posts, but had forgotten to set pause-on-start to 'true', so a number of unexpected things happened. I don't recall the details exactly, so suffice it to say that I could not get them both running. I simply swapped the 1080 into the upper slot, which also moved heat away from the two NVME ports on the system board. Then I repeated this with the GTX 1080 from Z805, whose main job in this ecosystem is spinning 6 x 4TB HDDs for backups, and was a very expensive way to support a GPU. After seeing how they go, I doubt that I would want to run a second GPU in these relatively small cases anyway, but some research on the net didn't yield anything particularly useful, so I thought it would be useful to ask here.

[muziqaz]

You create 2 slots, one for each GPU. And start folding.
Windows, Linux FAHclient v7 is the same

[appepi]

Golly, that sounded exactly what I had expected and had done when it all went pear-shaped a few nights earlier. It SHOULD be like that. So easy that I just HAD to try it again. 1.5 hours and half a dozen dumped jobs later I had the GTX 1080 working again. I started with the simple Fah setup with no CPU client and just the 1080. I paused the job. I shut down. I installed the P1000 in a PCIe3x4 slot. When I fired up Fah,7.6.21 it disabled the 1080 slot and started folding on a new slot for the P1000. Much the same as the first time as described in my original post, except that then the situation was reversed because the P1000 was the resident GPU and it was the 1080 being added: when I added a 1080 the P1000 slot was disabled and a 1080 job started.

I skip over the other attempts to get both running, up to and including uninstalling and reinstalling Fah and its data twice. I skip over the subsequent attempts to get the 1080 running again, which required re-installing its driver file. So OK. Once is an accident, twice is a coincidence, and five times means that it works for everyone else but not me/my hardware/7.6.21/W11/Australia/cold nights in Southern Hemisphere Winter/Thursdays etc. Possibly I have offended a daemon somewhere. But as far as I'm concerned it doesn't work that way.

[muziqaz]

First you need to find out if your system drivers are in order, then you need to see if FAHclient is seeing both GPUs, then try folding on both.
V7 system info tab screenshot would unveil a lot of things for those who are troubleshooting this
P.S. your condemned V8, does this automatically and much much simpler

[bollix47]

For nvidia on Windows you should install the drivers from:

www.nvidia.com/drivers

[appepi]

Thanks folks. Drivers were latest studio drivers downloaded from NVidia, installed within the last few days since these Z4G4s only arrived on 18th June, and then installed again after problems (with trying to get two GPUsFolding). I also tried several iterations of earlier studio drivers. HP Performance Manager showed the two GPUs, showed that they each had the driver I had installed.

There is something of a net literature on problems with getting two GPUs running in W11 so may not be a specific FaH problem. I am consulting Professor Youtube about this, for want of other information. I know I've done it with W10 back in the Dark Ages before I discovered the One True Purpose of GPU's viz FAH, and I don't recall any special grief, but that was a while back.

I will probably try V8.4.9 at some point, though the absence of a timer to trigger "Finish up and Stop" is a drawback. My current goal is to get a clean run for 3 x RTX 2060 (in Z440s) and 2x GTX 1080s (In Z4G4's) during off-peak (10pm-7am) rates, plus over-runs into "shoulder rates" (7am-2pm) as necessary to finish WUs, so I can work out if I can routinely run with this group within my $ limits for folding. It will be tight, so even an extra 2x 47W of P1000 might be too much. But at some point I will try again.

[bollix47]

I can't see anything at that link that says "studio drivers" but they might not work for folding .... you need to fill in the "Manual Driver Search" and download the full driver you need. RTX probably or GEforce.

[muziqaz]

Post the system info tab screenshot, especially the bottom bit

[appepi]

I can't see anything at that link that says "studio drivers" but they might not work for folding .... you need to fill in the "Manual Driver Search" and download the full driver you need. RTX probably or GEforce.

Yes, and when you select the GEForce 10 series and the GTX 1080, you are offered "Studio" or "Game Ready" options for 576.80 and when you choose the former and click View, you get to https://www.nvidia.com/en-us/geforce/dr ... ts/247854/ where you are told:

NVIDIA Studio Drivers provide artists, creators, and 3D developers the best performance and reliability when working with creative applications. To achieve the highest level of reliability, Studio Drivers undergo extensive testing against multi-app creator workflows and multiple revisions of the top creative applications from Adobe to Autodesk and beyond.

And certainly 576.80 works just fine for Folding with the 1080s. So tonight I decided to run a quick test in the half hour before folding time. With no folding happening, I added a P1000 in a PCI3x8 slot. Two screens plugged into the 1080, none into the P1000. When I restarted, ONE screen lit up. I checked HP Performance Adviser, which sees both cards and their drivers. I checked Windows device manager, which put a yellow triangle on the 1080 Display adapter and snarled: "This device is not working properly because Windows cannot load the drivers for the device (Code 31). The I/O device is configured incorrectly or the configuration parameters to the driver are incorrect." On the other hand it had no complaints about the P1000. I shut down, took out the P1000,fired up, reinstalled the 576.80 drivers just in case, and all is well again.

Post the system info tab screenshot, especially the bottom bit

Que? I am not sure which app's "system info" tab is at issue here, and how can I post a screenshot in this Forum?

[muziqaz]

Open FAH Advanced Control through systray icon right click. You will see 3 tab looking things, "Status", "System Info" and "Log". Click on system info, scroll down, take a screenshot, upload the screenshot to some online image storage, post a link to that stored image here

[appepi]

post a link to that stored image here

I have as little to do with external storage as possible, but let's see if my comparison of the cost per MPPD for the P1000, GTX1080, and RTX2060 makes it. Wattage is max for the GPU, PPD is from LARS GPU lists, cents per kWH is based on my upcoming "off-peak" rates in AU $ from 1 July 2025.
https://docs.google.com/document/d/e/2P ... a1nQFb/pub

This is a good reason for NOT adding expensive PPD from the P1000 to to much cheaper ones from the 1080, but I will try some ways of getting W11 to recognise two GPUs with different drivers that I saw suggested on the net, since a solution migh tbe useful to others.

[appepi]

First things first: here are the FahControl System Info pictures.

https://docs.google.com/document/d/e/2P ... C8uVG3/pub

The first one is running with just the GTX 1080, where all is well. The second one shows what happens when a P1000 is added and W11 refuses to activate the 1080. No idea why the OS is seen as W10 enterprise, but these were probably ex-corporate devices with that OS installed and the W11 installed on them was a free upgrade from it?

Further exploration made it clear, at least to me, that this is about Windows 11, which refused to allow two adapters to co-operate in Device Manager. Installing the P1000 would make the 1080 driver fail, and the P1000 would be OK, removing the P1000 would allow the (unchanged) 1080 driver to load just fine. Conversely, deleting the 1080 adapter in Drive Manager would allow the P1000 to function. I officially give up on this.

Foolishly, I decided to try a P1000 alongside the RTX2060 with W10 Pro in Z443, and have just spent some hours in a freezing attic getting my best folding device back on line after something I did - presumably moving the NVME-on-a-card-in-a-regular-PCIe-slot - led to failures curable only (at least for me) by resetting the system. This was not helped by the fact that Microsoft kept telling me that the relevant MS account didn't exist, though the email it sent codes to was the same email that should have given me access to the MS account and its purchases of standalone Office and 10 devices connected with it. It turned out that when I preserved my Skype account by transferring it to Teams, MS seems to have taken my ancient Skype login as owning the account with the same email, which was relegated to a secondary ID. So it was a useful exercise, I guess, when some combination of failures led MS to suggest that it would settle for my Skype ID and password, and I was able to reclaim the account, but currently I am so grateful to be able to fold with 1 GPU in 1 Box under W10 that I no longer wish to aggravate the gremlins by attempting more.

[muziqaz]

In order for you to fold on both GPUs, you need to create 1 slot for each of the GPUs.
In Advanced Control Click on Configure, then click on Slots tab.
Click Add
Tick GPU section. Under GPU-Index enter 0 (zero), same under opencl and cuda index. Click ok. List should show one GPU slot. Click Add again, tick GPU section. Under GPU-Index enter 1, same number should be entered under opencl and cuda index. click OK. click Save. Control should be showing 2 slots, each showing different GPU. Now you can start folding on both GPUs

[appepi]

Thx. I did that sort of setup, but always I have just taken whatever numbers it gave me, and what it gave me when I had two GPU's was a "-1" which seems to be code for a disabled GPU? Which I then presumed was the result of Windows Device Manager having problems with associating GPU and driver? I will add this to my "test" list alongside trying with 8.4.9. But probably not till next weekend.

[muziqaz]

-1 is automatic, and not disabled