PRIME offload users, how well does it work? Questions about igpu + prime offload

Fed up with desktop performance and I need X11 not to hang on trivial tasks. I ordered a 13700k (with an iGPU) and will use it to drive everything while using the RTX 3090 for what it is good - gaming, CUDA and video encoding/decoding.

Does everything work fine? What issues/limitations should I expect to encounter?

I know GSync won’t work, but with VRR working on the intel driver driving the GPU in a game rendered by Nvidia via PRIME, will it work?

i have a acer with an amd 5800h and nvidia 3060dgpu, its taken a bit of time to setup things properly. ive finally managed to set a bunch of environment variables at login to ensure nothing touches the nvidia dgpu so it can use D3 power management without being constantly woken up.

export VK_LOADER_DRIVERS_SELECT="*radeon_icd*"
export MESA_VK_DEVICE_SELECT="1002:1638"
export __EGL_VENDOR_LIBRARY_FILENAMES="/usr/share/glvnd/egl_vendor.d/50_mesa.json"
export __VK_LAYER_NV_optimus="non_NVIDIA_only"
export DRI_PRIME="0"
export LIBVA_DRIVER_NAME="radeonsi"
export VDPAU_DRIVER="radeonsi"
export WLR_RENDER_DRM_DEVICE="/dev/dri/renderD128"

then i essentially have an prime-run script in my $PATH that does



with the udev rules/module options etc setup as in Chapter 22. PCI-Express Runtime D3 (RTD3) Power Management

i also run a second monitor connected to hdmi but its hardwired to the nvidia dgpu. and i havent really managed to get things working satisfyingly on X11 it either lags to death doing so. or simply doesnt render unless i setup a convulated xorg.conf that runs everything on nvidia. luckily wayland seems to handle it better so ive been there for a while now. still havent figured out how to deal with vaapi/vdpau properly yet. and then there is various issues still of not being able to use half of the nvidia-settings options on wayland. like powermizer etc.

so uh it works, but its not pretty. then there is the normal range of bugs that seems to affect everyone as being posted in this forum. XID errors, broken vulkan extensions etc. if i would have been wiser before buying this i would have gotten an amd igpu + amd dgpu.

No. For VRR, the rendering gpu will have to be directly connected to the display.