Issue with Win 7 recognizing fourth video card...
ScarletX1969
Posts: 587
So, I have four NVIDIA cards running under Windows 7. 2x NVIDIA 760, 1x NVIDIA 940 GT, and 1x NVIDIA 1050Ti.
Want to play with this setup rendering in IRAY in Daz Studio. One 760 is my main video card, but the other three I wish to just use the CUDA cores for rendering.
However, Windows 7 will give me a Code43 error in the system properties, stating "Windows has stopped this device because it has reported problems". Throws this on the 940 GT.
There's nothing wrong with the card. Matter of fact, if I uninstall the current NVIDIA driver, it switches the error to either one of the 760s or the 1050Ti.
Has anyone else run into this issue and if so, what has been your solution?
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Comments
The first thing that I would check is your PSU. What make, model and capacity do you have?
Stupid question-- you have the right bridge installed correctly, yes?
I have an 850W PSU. Don't know the brand right off, but it's more than enough.
No question is stupid...when you say "right bridge", what do you mean?
I don't have SLI activated between these cards as that IRAY doesn't recognize it anyway, so there's not need for it.
tbh, im curious about your psu; you say it's enough yet don't know its name. just cause it says 850, doesn't mean it can deliver that.
Although, if the PSU was the issue, other things may be going wrong; have you checked that the card is getting power, plugged in correctly? Have you tried swapping cards between slots?
I don't know the brand name of the PSU; however, I know it 850W and it's been running 3 video cards and powering my MB, so I know it's solid. I've tried switch things around, still no luck.
If the issue only occurs when using 4 cards, switch to 3 cards. I realize it's not a 'solution' but if your 760 only has 2 GB of VRAM, you won't gain much benefit from it in DAZ Iray rendering anyway. Use the 3 remaining cards:
The amount of speed you'd gain by tossing the extra 760 into the mix would be negligible and scenes under 2 GB are not super common.
It has 4GB of VRAM and it's overclocked, but it only has about 384 CUDA cores, so it's not a big deal...I just wanted to run a four card setup since the board can support 4 cards. It could also be that these low-enders don't play well with the 940 and 1050TI. You're suggesting is something I was considering. Oh well...maybe I should just get two TITAN X or whatever cards and call it a night...lol
Make it 2x 1080TIs and you have yourself a deal! :)
You know it was 'solid' at supporting 3 cards.
Yes, it was 'solid' at supporting 3 cards. It's a Sentry Powerblade 850W PSU...and I think I found the problem. Old Display Link software was still installed on my machine and I think that was the culprit. When I took the card out, the 960 was still giving the error, even after a clean install of the drivers. But, when I uninstalled that software and rebooted, the error went away. So now I bet the card will work. I will try again at a later date.
There could be an issue with the drivers. So uninstall all then make a clean new install. Eventually get DDU and remove all NVidia drivers before reinstalling
Other factor : your combination of motherboard and processor doesn't allow to run so many cards. I guess you only have 16 PCIe lanes with your processor and depending on what other PCIe device you have, there may be not enough lanes left. I don't know if Nvidia allows PCIe 4x to run or if you need a minimum of 8x PCIe lanes
I did use DDU to do a completely clean install. But that last part of your post got me curious. Could you explain a little bit more?
The number of PCI-E lanes is dependent upon your CPU and motherboard. PCI-E cards and peripherals will use the lanes to increase the speed of transferring data across the PCI-E bus.
Graphics cards today can run at 16x lanes, 8x lanes, or 4x lanes (it's always a power of 2). Most won't go below 4x lanes. Most modern CPUs provide 20 lanes, some higher-end CPUs provide over twice that. But other peripherals can also use lanes. M.2 SSD drives use PCI-E lanes. Other built-in peripherals (on-board sound, network, etc.) can also use PCI-E lanes. The problem is you can run out of lanes, or have too few for what a given card requires. Then the card just won't work.
So with 4 PCI-E graphics card, that's 16 PCI-E lanes minimum.(4 at 4x lanes), which only leaves 4 lanes on a 20 lane CPU. If any on-board peripherals are using more than 4 lanes, there's a conflict, and one of the cards will probably not work.
Some motherboards also don't allow certain slots to run below a certain number of lanes (i.e., some gaming boards put the two main PCI-E slots at 16x/8x, and won't let them use less if they are occupied) specifically for graphics cards. So there's a lot of possible issues once you get up to 3+ graphics cards in the same machine, unless it was built to handle that many PCI-E lanes being needed. (Some XEON CPU's provide 40+ lanes, so running 4 graphics cards at 8x each isn't a problem......or running two at 16x.)
As you didn't mention what you have as processor and motherboard I'll take an example
If you have an intel 7700K you have a maximum of 16 PCIe lanes as written in Intel ARK https://ark.intel.com/products/97129/Intel-Core-i7-7700K-Processor-8M-Cache-up-to-4_50-GHz
For each device you add on a motherboard, it will need a certain number of PCIe lanes for communication
If you use a M.2 SSD disk you will already consume 4 lanes. Which leaves 12 lanes to use for gfx cards which is not enough to run 4 cards
Then you have the motherboard specs
If we take EVGA Z170 FTW Mobo you can see it has four mechanical PCIe x16 slots for Gfx cards http://www.evga.com/products/pdf/140-SS-E177.pdf
However ,in reality if you look at the PCIe arrangement supported it is written that it either support either one card at 16x speed or 2x8 + 1x4 + 1x1
If you make the count, two cards at x8 already take your 16 PCIe lanes but I think they use a PLX chip to send twice x8 datas. So in our example 8 PCIe lanes are in fact used
If you add a third Gfx card, the count goes up to 12 which is within your processor capacity
The last slot at x1 shouldn't work if you plug a graphic card (I'm not sure 4x works and 1x is even less probable).
If you look at the card spec, EVGA sells it as up to 2-way SLI which seems to confirm that you need at least 8x for SLI. As we don't need SLI for Iray, the 4x may work but that has to be confirmed
EVGA also sells another Motherboard that looks almost identical to the FTW http://www.evga.com/products/pdf/151-SS-E179.pdf
However that one supports four 8x for quad sli thanks to the PLX Chip but should need all 16 PCIe lanes for that, and prevent using M.2 SSD