Using dual GPUs effectively?

Hello,

Im using Davinci Resolve Studio 16b3

My PC:
Intel i7-8700K (6x 4.70 GHz Turbotakt, 12MB)
ASRock Z370 Extreme4
64GB DDR4 (4x16GB) PC3000 Corsair Vengeance
2x 8GB MSI GTX1070Ti ARMOR SLI

As im doing Fusion work and playing it back (3D Renderer is set to "Software Render") Resolve is only making use of one of my GPUs. As i play it back the usage of my first GPU is getting more and more with time while the usage of my second GPU is always staying the same at around 50%.
This wouldnt be a problem, but when my first GPU is maxed out it crashes and i get the massage "the GPU dailed to perform image processing because of an error (see picture of my first GPU, in the background you can see the increasing usage)

Is there any possibility to get Resolve to use both GPUs at the same amount?

Thanks and best regards,
Carlo

Turn SLI-OFF

and if using one of the GPUs to drive your monitors, check Use GPU for computer


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As im doing Fusion work and playing it back (3D Renderer is set to "Software Render") Resolve is only making use of one of my GPUs. As i play it back the usage of my first GPU is getting more and more with time

but when my first GPU is maxed out it crashes and i get the massage "the GPU dailed to perform image processing because of an error (see picture of my first GPU, in the background you can see the increasing usage)

Having the same problem with 16b3 despite having only one GPU. Might be a bug.

Hello,

thanks for your answeres!

Im afraid it did not improve anything.
I turned off SLI and checked the "Use GPU for computer" option.

My first GPU RAM is getting maxed out, my second GPU RAM is only used at around 40% all the time.

Anyone has another idea how to improve the usage of my GPU memory?

Thanks and best regards, Carlo

As a dual GPU user I am curious about this too? Is this a Resolve 16 Beta 3/4 bug or is Fusion in Resolve just not supposed to use more than 1 GPU. The error when the one GPU maxes out is concerning as well but I haven't run into that one.

I wonder if the devs are aware of this issue. If not it may be a good idea to post it in the Resolve 16 beta forum so the team at Black Magic has a chance to look into it, or at least clarify what might be going on.

Well, its the same in Resolve 15. It seems that Resolve at all is just not able to utilize dual GPUs at its full potential.

This is a quote from The "Hardware Selection and Configuration Guide" of Davinci Resolve 15:

High performance GPUs or multiple GPUs will offer the best experience

Which im my opinion is just a complete misinformation. I read this, got a second GPU and it does not work at all!!!

If they know about it? I dont know, they are predenting to read the users problems here, but at least they did not change a thing about it and are not helping me here at all...

Curious...

Before I had 2 GPUs that I managed to ride in load. Not all the time but with Davinci Resolve often.
First condition to install the correct driver: NVIDIA 430.86 NSD

Can you confirm no other monitors or devices connected to your second GPU?

jPo, CSI

Hi

Your cpu i a coffee lake i7 8700K
Memory channels max # 2
pci lanes max # 16

You got 4×16gb ram !

2 x 1070 use 2x 16x - you only got 1x 16x - your 2 x 1070 will run x8 speed !

Curious...

Before I had 2 GPUs that I managed to ride in load. Not all the time but with Davinci Resolve often.
First condition to install the correct driver: NVIDIA 430.86 NSD

Thanks, I'm using this driver already

Can you confirm no other monitors or devices connected to your second GPU?

jPo, CSI

Yes, both monitors are connected to my first card

Hi

Your cpu i a coffee lake i7 8700K
Memory channels max # 2
pci lanes max # 16

You got 4×16gb ram !

2 x 1070 use 2x 16x - you only got 1x 16x - your 2 x 1070 will run x8 speed !

Do not really understand what this means - does it explain why my second card is only used at maximum of 50% while my first card is at full usage? (See pictures below)

This is a quote from The "Hardware Selection and Configuration Guide" of Davinci Resolve 15:

High performance GPUs or multiple GPUs will offer the best experience

Hi.

I am afraid, that I read the above different, than you have read it. I read it as for the CPU and GPU described in the Configuration Guide" of Davinci Resolve 15 can 'High performance GPUs or multiple GPUs offer the best experience'. Neither your Intel i7-8700K CPU or your GTX1070Ti's are described or recommended in the Configuration Guide.

But, 'will offer the best experience' don't mean a general speed increase for all the functions in Resolve. What its mean is that a few special functions as Noise Reduction will be faster with the right hardware.
And it will NOT run at the double speeds. Here is a link to DaVinci Resolve 14 GPU Scaling Analysis (1-4x Titan Xp):

https://www.pugetsystems.com/labs/artic ... n-Xp-1060/

As You can see are the speed increase for 2nd and 3rd GPU in an average 25-35% performance gain.

I can remember one or two years back, an another thread where an Australien User tried dual GTX 1070 in a Threadripper X399 motherboard. He was not successful either. I tried to search for this old thread, but are not able to find it. But I expect your problems are related to the GTX 1070 have a CUDA Performance below recommendation.

Regards Carsten.

Also, don't use the Windows task manager for monitoring GPU usage. It doesn't measure everything when you are using resolve. I found a lot of difference when rendering and monitoring with it and compared to GPU-Z values for example. I suggest to use different more reliable software for monitoring your GPU usage.

@Carlo Tassler

Do you have the Studio version?

When you installed the 430.86 NSD driver, did you ask for a clean install?

The 2 Gpus are well recognized in Davinci Resolve => preference => Memory & GPU?

Did you try to force GPU Processing 'Auto' to 'CUDA' + Use display GPU for compute ON or OFF

@Carsten Sellberg

Well, i still find it very misleading. A single 1080TI would have given me a better experience than my dual 1070TI (and it would have been cheaper) so just "High performance GPUs will offer the best experience" would be more correct.

@Jean Claude & @ChipKng

Im using the Studio Version and both GPUs are recognized in the settings.
I just upgraded to 16b5 and i dont know if this made the change, but now my first GPU usage is staying at a contant level, so its not getting "maxed out" and there is no more crash. It just keeps playing the fusion composition in a loop on and on! Thats so awesome! It also feels a little more fluid

Thank you all so much for your help - for me this seems to be fixed.
So, im using the recommended driver here (NVIDIA 430.86 NSD), SLI is turned on, the GPU processing mode is Auto.

Hey,
Just a word to tell you I've never ever seen great performance in Fusion with an nVidia card, whatever HW config it's on... Even in the standalone version.
I really love it and searched among all these long threads showing OpenCL tweaks tests etc etc. One GPU or 2, any computer, system etc... Never.
On the other hand, Resolve Studio itself instantly took advantage of a second GPU when "use GUI blabla to compute" is ticked.
But never Fusion nor ReFusion.
So the "single card is enough" way is right for Fusion, not at all for Resolve imho.