Nvidia GPU priority + AMD primary card

Thu Jul 23, 2015 9:05 am

Hi guys,

So I'm having trouble being able to work on my system whilst Octane is rendering.

I've tried changing the rendering priority to low on my 2 x NVIDIA GeForce GTX 980 4GB cards and it just doesn't seem to make any difference to the speed at which I can work on other things. ... Isn't the point is of this function to allow for GPU to be available for other processes? ...There is a terrible lag from when I click on an object and when it actually gets selected. I need to be able to render whilst editing my scene at the same time.

Is there anything else that I can do to keep Cinema 4D working whilst the cards are rendering?

Also, I wondered if you you guys would know if its possible to get a system that could have one graphics card dedicated to running the rest of my PCs GPU based processes (say an AMD card) and uses the other two Nvidia GTX cards for Octane. This extra card would need to be in slot one of the machine of course. Would Octane still recognise my GTX cards in slots two and three? What do you recommend?

Cheers,
Luke.

Thu Jul 23, 2015 9:27 am

ex. I'm working with two 780. you should select priority on card which is connected to monitor. if you do this you can work without any noticable lags. but this also depends to scene. if you have a scene with hundreds objects, instances and big displacement it can cause more stress. so you can disable system gpu completely and work without any lag. as I said this is related to what kind of rendering and content.

Thu Jul 23, 2015 10:23 am

just install all the drivers and connect the monitor to the amd card, octane will recognize all the nvidia cards and you will be able to use them smoothly while the amd card is rendering the screen viewports

Thu Jul 23, 2015 11:02 am

so you can disable system gpu completely and work without any lag.

I don't follow you here I'm afraid.... how will disabling system GPU mean I get no lag working in C4D?

Thu Jul 23, 2015 11:05 am

you should select priority on card which is connected to monitor

No, this produces no noticeable or useful difference in lag at all. I honestly don't get what the priority settings do... they have no effect on anything except that when I lower the priority, I get longer render times...

I do have a scene which is quite dense in geometry, BUT my whole system is almost completely unresponsive, if I want view another window in another program, it takes ages for the system to respond. So how is this related to how heavy my scene is when it isnt Cinema 4D - I am not just talking about moving round the scene here.

whersmy wrote:just install all the drivers and connect the monitor to the amd card, octane will recognise all the nvidia cards and you will be able to use them smoothly while the amd card is rendering the screen viewports

This is great to know! I'll get on it right away as it seems like the only solution.

Thu Jul 23, 2015 12:07 pm

Hey there,

I'm trying to change the priority of my cards so that I can use some GPU for the rest of my system and no matter what settings I change in the priorities tab nothing changes in the speed at which the rest of my system operates. I also just tried turning off all my graphics cards to see what effect it would have on my render and it seemed to have no effect at all... its rendering as if nothing has changed!

Are there other settings for this?

I would upload an image but i keep getting 'could not upload attachment to files/....'

Thu Jul 23, 2015 12:19 pm

are talking about Live viewer rendering with small size or a big render(3-4k) on picture viewer?

Thu Jul 23, 2015 12:34 pm

aoktar wrote:are talking about Live viewer rendering with small size or a big render(3-4k) on picture viewer?

Hi Aoktar,

I've realised that in the live viewer changing the GPU priorities works fine - It does have some effect on the speed of the rest of my system.

I find that when I send a render to the picture viewer (1920/1080) my system is really slow. I turned off 'use all GPUs' in the render settings so that I can only render with 1 GPU. But I still find there is lag when I try to move windows around and do other things. It is a bit better than when both GPUs are being used but not great.

One other thing - the 'Gpu stats' do not always show in the live viewer... i think this is a bug.

Thu Jul 23, 2015 12:37 pm

First that's not a bug. Check four parameters about stats. Also i couldn't get expected answer yet. What's the render sizes on Picture Viewer. If it's much bigger than LV's that can be expected behaviour.

Thu Jul 23, 2015 1:21 pm

aoktar wrote:First that's not a bug. Check four parameters about stats. Also i couldn't get expected answer yet. What's the render sizes on Picture Viewer. If it's much bigger than LV's that can be expected behaviour.

As I said, I rendering in the picture viewer at 1920/1080. It makes my system very slow and even when I reduce the priority its too slow to work. Even stopping a render is difficult because the option take so long to appear on screen. Sometimes it feels like cinema 4d is not responding at all.