This page will help you configure V-Ray for GPU rendering. For help with common questions, please see the V-Ray GPU Frequently Asked Questions page.
V-Ray GPU has a number of advantages:
V-Ray CPU advantages:
V-Ray GPU offers rendering with NVIDIA CUDA platform.
Below is a list of tests we have performed and the results:
Rendering on multiple GPUs is supported and by default IPR for GPU will use all available CUDA devices. See the sections below how to choose devices to run IPR GPU on.
If V-Ray GPU cannot find a supported GPU device on the system, it will silently fall back to CPU code. To see if the V-Ray render server is really rendering on the GPU, check out its console output.
When rendering, the V-Ray progress log provides information about your current driver version. If the version is not compatible with V-Ray GPU, you will find a message with the recommended version.
Unsupported driver version and recommendation to upgrade
Тo use NVLINK on supported hardware, NVLINK devices must be set to TCC mode. This is recommended for Pascal, Volta and Turning-based Quadro models. For GeForce RTX cards, a SLI setup is sufficient. Also note that to prevent performance loss, not all data is shared between devices.
Though GPU rendering with CUDA on MacOS devices is no longer supported, the advanced users can bring back the old behavior by using the following environment variable: VRAY_APPSDK_UNHIDE_DEVICES=1. Chaos Group does not guarantee the functionality and quality of the GPU engine if you choose to proceed with using this environment variable.
You may not want to use all available GPU devices for rendering, especially if you have multiple GPUs and you want to leave one of them free for working on the user interface or you may want to combine your CPU and GPU together (see the Hybrid Rendering section below).
There are two ways to do this: by using the supplied standalone device selection tool, accessible from both the V-Ray Tools menu and the Start menu search, or from the Asset Editor's GPU device dropdown list.
When selecting devices from the standalone tool, that will set the default setup for the work station. After changing this option, you need to restart SketchUp and/or any Standalone DR servers (if any are running) for the changes to take effect. If the Standalone DR server is running as a service, you may need to restart it.
The GPU Device Selection tool is not available on Mac OS X.
When choosing the devices from the Asset Editor - it is done only for the current session in SketchUp.
If you see your CPU listed twice, choose the option with "C++/CPU " in the name.
Starting in 3.60, V-Ray GPU can perform hybrid rendering with the CUDA engine utilizing both the CPU and NVIDIA GPUs. V-Ray can now execute the CUDA source on the CPU, as though the CPU was another CUDA device. To enable the hybrid rendering mode, simply enable the C++/CPU device from the list of CUDA devices.
The hybrid rendering mode does not require any special drivers. Furthermore, you can use the CPU as a CUDA device even if you don't have an NVIDIA GPU and/or NVIDIA drivers installed. Meaning, this mode can be used on computers that don't even have GPUs. The hybrid render engine running on a CPU supports the same features as the regular V-Ray GPU CUDA engine.
More info about the nature of Hybrid rendering is available at the blog post Understanding V-Ray Hybrid rendering.