# Render node not using CPU with Hybrid CUDA Rendering **URL:** \ **Category:** Issues\ **Created:** [August 15, 2019, 12:50pm UTC](https://forums.chaos.com/t/render-node-not-using-cpu-with-hybrid-cuda-rendering/95259 "2019-08-15T12:50:27Z")\ **Posts on this page:** 15\ **Page:** 1
**Author:** ![sebbiej](https://dub1.discourse-cdn.com/chaosprd/user_avatar/forums.chaos.com/sebbiej/32/58160_2.png) [@sebbiej](https://forums.chaos.com/u/sebbiej)\ **Post date:** [August 15, 2019, 12:50pm UTC](https://forums.chaos.com/t/render-node-not-using-cpu-with-hybrid-cuda-rendering/95259/1 "2019-08-15T12:50:27Z")
Hi guys, I’ve got a little issue with rendering via Backburner: I’ve set a couple of scenes to use CUDA GPU + CPU, when I send the scene to Backburner it uses both the CPU and GPU on my local PC, but on an identical render node PC it only seems to use the GPU, the CPU is ignored. Would anybody know why this may be? Both PCs are running windows 10, Maya 2018.6, and Vray Next 4.12.01 ---
**Author:** ![Zdravko.Keremidchiev](https://dub1.discourse-cdn.com/chaosprd/user_avatar/forums.chaos.com/zdravko.keremidchiev/32/48745_2.png) [@Zdravko.Keremidchiev](https://forums.chaos.com/u/Zdravko.Keremidchiev)\ **Post date:** [August 16, 2019, 8:10am UTC](https://forums.chaos.com/t/render-node-not-using-cpu-with-hybrid-cuda-rendering/95259/2 "2019-08-16T08:10:11Z")
Have you enabled C++/CPU on the slave machines, in the Select devices for V-RayGPU rendering tool? ---
**Author:** ![sebbiej](https://dub1.discourse-cdn.com/chaosprd/user_avatar/forums.chaos.com/sebbiej/32/58160_2.png) [@sebbiej](https://forums.chaos.com/u/sebbiej)\ **Post date:** [August 23, 2019, 10:30am UTC](https://forums.chaos.com/t/render-node-not-using-cpu-with-hybrid-cuda-rendering/95259/3 "2019-08-23T10:30:40Z")
Ah, that did it! It wasn’t enabled in the GPU options… Many thanks for the fix! ---
**Author:** ![Zdravko.Keremidchiev](https://dub1.discourse-cdn.com/chaosprd/user_avatar/forums.chaos.com/zdravko.keremidchiev/32/48745_2.png) [@Zdravko.Keremidchiev](https://forums.chaos.com/u/Zdravko.Keremidchiev)\ **Post date:** [August 23, 2019, 2:20pm UTC](https://forums.chaos.com/t/render-node-not-using-cpu-with-hybrid-cuda-rendering/95259/4 "2019-08-23T14:20:10Z")
You are welcome ---
**Author:** ![sebbiej](https://dub1.discourse-cdn.com/chaosprd/user_avatar/forums.chaos.com/sebbiej/32/58160_2.png) [@sebbiej](https://forums.chaos.com/u/sebbiej)\ **Post date:** [November 11, 2019, 10:38am UTC](https://forums.chaos.com/t/render-node-not-using-cpu-with-hybrid-cuda-rendering/95259/5 "2019-11-11T10:38:54Z")
> [@Zdravko.Keremidchiev](#): > > You are welcome Hi, I seem to be having an issue with this again: My render slave PC has got both the CPU and the GPU (GTX 1060) set to render in the “Select Devices for V-Ray GPU Rendering” tool, but it isn’t rendering on the CPU on the slave. I’ve attempted restarting and updating the graphics card drivers to the latest studio releases (matching on both identical PCs). ---
**Author:** ![sebbiej](https://dub1.discourse-cdn.com/chaosprd/user_avatar/forums.chaos.com/sebbiej/32/58160_2.png) [@sebbiej](https://forums.chaos.com/u/sebbiej)\ **Post date:** [December 3, 2019, 9:26am UTC](https://forums.chaos.com/t/render-node-not-using-cpu-with-hybrid-cuda-rendering/95259/6 "2019-12-03T09:26:05Z")
…I’m still having this error, despite having the CPU and GPU set to be used in the “Select Devices for V-Ray GPU Rendering” tool 😕@Zdravko.Keremidchiev ---
**Author:** ![Zdravko.Keremidchiev](https://dub1.discourse-cdn.com/chaosprd/user_avatar/forums.chaos.com/zdravko.keremidchiev/32/48745_2.png) [@Zdravko.Keremidchiev](https://forums.chaos.com/u/Zdravko.Keremidchiev)\ **Post date:** [December 3, 2019, 1:12pm UTC](https://forums.chaos.com/t/render-node-not-using-cpu-with-hybrid-cuda-rendering/95259/7 "2019-12-03T13:12:53Z")
I’m sorry for the late reply. Would it be possible to send us an e-mail ([support@chaosgroup.com](mailto:support@chaosgroup.com)) so we could arrange a team-viewer session and check thigs first hand. Please make sure to mention this thread in your e-mail. ---
**Author:** ![GARY\_ROYLANCE](https://dub1.discourse-cdn.com/chaosprd/user_avatar/forums.chaos.com/gary_roylance/32/70114_2.png) [@GARY\_ROYLANCE](https://forums.chaos.com/u/GARY_ROYLANCE)\ **Post date:** [October 25, 2020, 6:36pm UTC](https://forums.chaos.com/t/render-node-not-using-cpu-with-hybrid-cuda-rendering/95259/8 "2020-10-25T18:36:33Z")
Was there any resolution to this problem? I’m having the same issue with Vray 5 for Mays, the local machine uses CPU and GPU but my two render nodes only use their GPU’s. Thanks ---
**Author:** ![sebbiej](https://dub1.discourse-cdn.com/chaosprd/user_avatar/forums.chaos.com/sebbiej/32/58160_2.png) [@sebbiej](https://forums.chaos.com/u/sebbiej)\ **Post date:** [October 26, 2020, 10:42am UTC](https://forums.chaos.com/t/render-node-not-using-cpu-with-hybrid-cuda-rendering/95259/9 "2020-10-26T10:42:30Z")
> [@GARY\_ROYLANCE](#): > > Was there any resolution to this problem? > > I’m having the same issue with Vray 5 for Mays, the local machine uses CPU and GPU but my two render nodes only use their GPU’s. > > Thanks I’m afraid I can’t remember now, I guess you could try and make sure you’ve got identical versions of Vray on both your master and slave PCs, with the same version of the license server too. Sorry that I can’t be of more help! ---
**Author:** ![GARY\_ROYLANCE](https://dub1.discourse-cdn.com/chaosprd/user_avatar/forums.chaos.com/gary_roylance/32/70114_2.png) [@GARY\_ROYLANCE](https://forums.chaos.com/u/GARY_ROYLANCE)\ **Post date:** [October 26, 2020, 11:33am UTC](https://forums.chaos.com/t/render-node-not-using-cpu-with-hybrid-cuda-rendering/95259/10 "2020-10-26T11:33:43Z")
> [@sebbiej](#): > > I’m afraid I can’t remember now, I guess you could try and make sure you’ve got identical versions of Vray on both your master and slave PCs, with the same version of the license server too. Sorry that I can’t be of more help! All the versions are identical, all Windows 10 Pro machine, network is 10Gbe, Nvidia Drivers all the same. Baffling as the Vray Next Benchmark uses the GPU and CPU at 100% on each. Does yours work now? Thanks ---
**Author:** ![Zdravko.Keremidchiev](https://dub1.discourse-cdn.com/chaosprd/user_avatar/forums.chaos.com/zdravko.keremidchiev/32/48745_2.png) [@Zdravko.Keremidchiev](https://forums.chaos.com/u/Zdravko.Keremidchiev)\ **Post date:** [October 26, 2020, 11:49am UTC](https://forums.chaos.com/t/render-node-not-using-cpu-with-hybrid-cuda-rendering/95259/11 "2020-10-26T11:49:54Z")
Did you double-check whether you have enabled C++/CPU on the slave machines, in the Select devices for V-RayGPU rendering tool? If that is not the case I would advise you to write us an e-mail so we could arrange a team-viewer meeting. ---
**Author:** ![GARY\_ROYLANCE](https://dub1.discourse-cdn.com/chaosprd/user_avatar/forums.chaos.com/gary_roylance/32/70114_2.png) [@GARY\_ROYLANCE](https://forums.chaos.com/u/GARY_ROYLANCE)\ **Post date:** [October 26, 2020, 4:43pm UTC](https://forums.chaos.com/t/render-node-not-using-cpu-with-hybrid-cuda-rendering/95259/12 "2020-10-26T16:43:18Z")
> [@Zdravko.Keremidchiev](#): > > Did you double-check whether you have enabled C++/CPU on the slave machines, in the Select devices for V-RayGPU rendering tool? If that is not the case I would advise you to write us an e-mail so we could arrange a team-viewer meeting. Hi, Yes all setup to use GPU and CPU on each each slave and the local workstation. ---
**Author:** ![Zdravko.Keremidchiev](https://dub1.discourse-cdn.com/chaosprd/user_avatar/forums.chaos.com/zdravko.keremidchiev/32/48745_2.png) [@Zdravko.Keremidchiev](https://forums.chaos.com/u/Zdravko.Keremidchiev)\ **Post date:** [October 28, 2020, 2:51pm UTC](https://forums.chaos.com/t/render-node-not-using-cpu-with-hybrid-cuda-rendering/95259/13 "2020-10-28T14:51:01Z")
Do you use NVLink and which V-Ray version is this? ---
**Author:** ![GARY\_ROYLANCE](https://dub1.discourse-cdn.com/chaosprd/user_avatar/forums.chaos.com/gary_roylance/32/70114_2.png) [@GARY\_ROYLANCE](https://forums.chaos.com/u/GARY_ROYLANCE)\ **Post date:** [November 13, 2020, 7:28am UTC](https://forums.chaos.com/t/render-node-not-using-cpu-with-hybrid-cuda-rendering/95259/14 "2020-11-13T07:28:45Z")
> [@Zdravko.Keremidchiev](#): > > Do you use NVLink and which V-Ray version is this? I don’t use NVLink and it is Vray 5 for Maya ---
**Author:** ![Zdravko.Keremidchiev](https://dub1.discourse-cdn.com/chaosprd/user_avatar/forums.chaos.com/zdravko.keremidchiev/32/48745_2.png) [@Zdravko.Keremidchiev](https://forums.chaos.com/u/Zdravko.Keremidchiev)\ **Post date:** [November 23, 2020, 9:32am UTC](https://forums.chaos.com/t/render-node-not-using-cpu-with-hybrid-cuda-rendering/95259/15 "2020-11-23T09:32:52Z")
In this case, please send us an e-mail to support at chaosgroup so we could arrange a Teamviewer session and check the issue first hand.