Right now NixOS puts a lot of Xorg-level video drivers into the default configuration. It looks like having intel creates problems now that we have Xorg 1.20.
(I am not using NixOS but I do use the NixOS xorg.conf generation code)
Xorg 1.20 has updated many things. In particular it broke Nvidia binary driver ABI compatibility (to the surprise of no one) and a popular suggestion on the forums is «just use Nouveau». On my Intel+Nvidia Thinkpad I have happily used Nouveau for a long time already with XRandR offload, but Xorg 1.20 still broke my configuration. After some more debugging and log-comparing and web-searching, it looks like:
i915/intel for Intel card + nouveau/modesetting for Nvidia leads to working built-in display, but broken VGA output (offloading doesn't work properly, although the colour range of the garbage on the screen seems roughly correct, and the mouse pointer works for some weird reason).
videoDrivers = mkForce ["modesetting"]; solves the visible problems, modesetting is used correctly for both outputs, xrandr works.
(as a side note: when building only the Xorg service, apparently two LLVM builds are necessary — maybe it was fixed since Xorg 1.20 bump, though)
Right now NixOS puts a lot of Xorg-level video drivers into the default configuration. It looks like having
intelcreates problems now that we have Xorg 1.20.(I am not using NixOS but I do use the NixOS
xorg.confgeneration code)Xorg 1.20 has updated many things. In particular it broke Nvidia binary driver ABI compatibility (to the surprise of no one) and a popular suggestion on the forums is «just use Nouveau». On my Intel+Nvidia Thinkpad I have happily used Nouveau for a long time already with XRandR offload, but Xorg 1.20 still broke my configuration. After some more debugging and log-comparing and web-searching, it looks like:
i915/intelfor Intel card +nouveau/modesettingfor Nvidia leads to working built-in display, but broken VGA output (offloading doesn't work properly, although the colour range of the garbage on the screen seems roughly correct, and the mouse pointer works for some weird reason).videoDrivers = mkForce ["modesetting"];solves the visible problems,modesettingis used correctly for both outputs,xrandrworks.(as a side note: when building only the Xorg service, apparently two LLVM builds are necessary — maybe it was fixed since Xorg 1.20 bump, though)