GPU issues with the VMware Horizon Indirect Display Driver

You may experience GPU issues with the VMware Horizon Indirect Display Driver in your environment when using 3rd party applications which incorrectly utilize the incorrect display adapter. This results with the inability to use and/or run GPU accelerated workloads including VDI, AI, and ML.

This issue effects NVIDIA vGPU (both vGPU and vDGA passthrough), AMD MxGPU, and Intel Data Center GPU Flex GPUs using SR-IOV, in any deployment where the VMware Indirect Display Driver is installed.

When this issue occurs, the application will incorrectly query the capabilities of the VMware Indirect Display Adapter instead of the GPU that is presented to the VM, resulting in a scenario where the application isn’t aware of the capabilities of the GPU you are utilizing, failing to utilize the GPU, and hardware acceleration, such as hardware encoding (NVENC) and hardware decoding.

What is the VMware Horizon Indirect Display Driver

The VMware Horizon Indirect Display Driver, also known as the VMware Indirect Display Driver, is a “virtual” display driver that isn’t bound to a specific hypervisor, and works with many deployments because of the lack of that limitation.

This driver is installed with the VMware Horizon agent, and can work in conjunction with hardware acceleration, including GPUs (such as NVIDIA vGPU, AMD MxGPU, and Intel Data Center GPUs using SR-IOV).

Under normal circumstances, the VMware Horizon Indirect Display Driver is prioritized as a fallback driver for remoting protocols, except in environments where no hypervisor or GPU display drivers are available (like Horizon Cloud on Azure) in which case it would become the priority.

The Problem

Applications designed to use a GPU, may not be able to correctly identify which display adapter to use on the VM. While you may have a GPU, vGPU, or 3D acceleration in your environment, the application may be unaware of the device and/or its capabilities.

This is caused by the application either not correctly using the preferred primary display adapter (GPU and/or vGPU), or not being designed to handle multiple display adapters (and drivers).

Example Scenario:

When using CyberLink PowerDirector 360 in a VMware Horizon environment with an NVIDIA vGPU, the application will query the VM’s Windows instance for hardware acceleration capabilities, specifically hardware encoding, hardware decoding, and use of APIs like NVIDIA’s NVENC encoder. In this scenario, while the VM does have an NVIDIA vGPU workstation profile attached with a valid NVIDIA RTX Virtual Workstation (vWS) license, the application is only aware of the VMware Indirect Display Driver and it’s capabilities. This results in all hardware accelerated encoding and decoding capabilities to be disabled.

Example Symptoms

• 3D Acceleration not detected by application
• CUDA Cores not available for application
• OpenCL not available
• DirectX and Direct3D usage unavailable

In all scenarios, the VM will appear to have 3D acceleration, however one or multiple applications won’t have access.

The Solution

Thanks to the design of the VMware Indirect Display Driver, it should be prioritized in a fashion that it’s used only when other display drivers aren’t available (including NVIDIA vGPU), or system resources aren’t available; however, some 3rd party application may not be able to reference the prioritization, or support multi-GPU (multi display driver), resulting in the incorrect display adapter being used.

As a workaround, you can remove the VMware Indirect Display Driver from the Windows instance running in the VM.

Please note that simply disabling the “VMware Horizon Indirect Display Driver” will not suffice. A full removal (Right Click, “Uninstall Device”) is required to workaround this issue. Additionally, upgrading or re-installing the VMware Horizon Agent will re-install the VMware Indirect Display Driver.

Additional Links and Resources

• NVIDIA vGPU Troubleshooting Guide (Stephen Wagner)
• Using the VMware Indirect Display Driver on Windows Desktops (VMware By Broadcom)