Fix DirectX 12 Support on VM with Nvidia L4 GPU Issue

When running a Virtual Machine (VM) with an NVIDIA L4 GPU and encountering the message “DirectX 12 is not supported on your system,” there are several potential causes and solutions. This issue typically arises due to the complexities of GPU virtualization and the configuration of the VM environment. Here’s how you can address and resolve this problem:

Understanding the Problem

DirectX 12 is a graphics API commonly used for rendering in applications and games. For a VM to support DirectX 12, several components must work together:

1. GPU Passthrough or vGPU Support: The NVIDIA L4 GPU must be properly passed through to the VM or configured as a virtual GPU (vGPU).
2. Compatible Drivers: The VM must have the correct NVIDIA drivers installed that support DirectX 12.
3. Operating System Compatibility: The guest OS must support DirectX 12, which usually means it should be Windows 10 or later.
4. Hypervisor Configuration: The hypervisor must support and correctly configure the GPU for use by the VM.

Steps to Diagnose and Fix the Issue

1. Verify GPU Passthrough or vGPU Configuration

Ensure that the NVIDIA L4 GPU is correctly configured for passthrough or vGPU in the hypervisor. Here’s how to check and set this up:

1. Passthrough Setup:

• Check that the GPU is assigned to the VM without conflicts. The PCI device should be passed through correctly.
• Use commands like lspci on the host to ensure the GPU is visible and bound to the correct driver (typically vfio-pci for passthrough).

2. vGPU Setup:

• For vGPU configurations, ensure that the VM is assigned a virtual GPU profile that supports DirectX 12. NVIDIA’s vGPU manager should show the vGPU assignment.
• Use nvidia-smi on the host to check vGPU allocations.

2. Install or Update NVIDIA Drivers on the VM

The VM must have the correct NVIDIA drivers installed to utilize DirectX 12. Follow these steps:

1. Download the Latest Drivers:

• Visit the NVIDIA Driver Download page and download the appropriate driver for the NVIDIA L4 GPU and your Windows version.

2. Install the Driver:

• Run the installer inside the VM and follow the instructions to complete the installation.

3. Verify Driver Installation:

• After installation, check the driver status by running nvidia-smi inside the VM. This should list the GPU and show its current status and capabilities.

3. Verify DirectX Version on the VM

Ensure that the VM’s operating system supports DirectX 12:

1. Check DirectX Version:

• Open the Run dialog (Win + R) and type dxdiag, then press Enter. This opens the DirectX Diagnostic Tool.
• In the System tab, check the DirectX version at the bottom. It should say “DirectX 12” if supported.

2. Update Windows:

• Ensure the VM’s Windows OS is fully updated. Go to Settings > Update & Security > Windows Update and check for updates.

4. Configure the Hypervisor

The hypervisor must be configured to support GPU usage by the VM:

1. Check Hypervisor Settings:

• Ensure that GPU acceleration is enabled in the hypervisor settings.
• In hypervisors like VMware, make sure 3D acceleration is enabled for the VM.

2. Review Hypervisor Documentation:

• Each hypervisor (VMware, KVM, Hyper-V, etc.) has specific settings for GPU passthrough or vGPU. Review the documentation to ensure all settings are correct.

5. Validate and Test

After making the above changes, test the DirectX 12 support:

1. Run dxdiag Again:

• Open the DirectX Diagnostic Tool to confirm that DirectX 12 is now supported.

2. Test with a DirectX 12 Application:

• Run a DirectX 12-compatible application or game to ensure it launches and runs without errors.

Additional Considerations

• Windows and DirectX Versions: If you’re using an older version of Windows (such as Windows 7 or Windows 8), DirectX 12 is not supported. Upgrade to Windows 10 or later.
• Driver Conflicts: Ensure no other conflicting drivers are installed on the VM that could interfere with the NVIDIA driver.
• Hypervisor Limitations: Some hypervisors have limitations or specific requirements for supporting advanced GPU features. Ensure your hypervisor version supports GPU passthrough or vGPU with the desired capabilities.

Conclusion

DirectX 12 enables developers to add graphics to applications and games. When there is a message that says “DirectX 12 is not supported on your system” at the time of running the virtual machine with an NVIDIA L4 GPU, which is the best GPU dedicated server, you can face multiple issues. To resolve this issue, you can configure vGPU, install the correct drivers, and ensure that the guest OS supports DirectX 12. If there is any issue, you can contact the administrator for support.