#houdini #linux ![[Houdini-21.png]] When running **Houdini 21** on a hybrid laptop with **Intel UHD Graphics + NVIDIA RTX**, I kept hitting Vulkan errors and falling back to OpenGL. The issue turned out to be Houdini not picking up the right Vulkan and OpenCL runtime. On **Fedora 42**, the simplest fix was to install Intel’s Vulkan and OpenCL packages and force Houdini to use them. ``` sudo dnf install mesa-vulkan-drivers mesa-vulkan-drivers.i686 intel-compute-runtime ``` Then, start Houdini with: ``` VK_ICD_FILENAMES=/usr/share/vulkan/icd.d/intel_icd.x86_64.json /opt/hfs21.0.440/bin/houdini ``` This command explicitly tells Houdini to use the **Intel Vulkan ICD** and the **Intel OpenCL GPU platform**, which resolves the fallback error and allows the viewport to run correctly on the Intel GPU. Rendering (Karma XPU, Redshift, etc.) still happens on the **NVIDIA RTX GPU**, this approach keeps the viewport stable under Wayland and avoids Vulkan initialization failures.