I got it working by reinstalling the kernel and nvidia-dkms and forcing mkinitcpio to regenerate the kernel image.
]]>With 410, the dkms builds fine but when I reboot I can't start the X session
Snippet from /var/lib/gdm/.local/share/xorg/Xorg.0.log
[ 8.296] (II) LoadModule: "nvidia"
[ 8.296] (II) Loading /usr/lib/xorg/modules/drivers/nvidia_drv.so
[ 8.302] (II) Module nvidia: vendor="NVIDIA Corporation"
[ 8.302] compiled for 4.0.2, module version = 1.0.0
[ 8.302] Module class: X.Org Video Driver
[ 8.303] (II) NVIDIA dlloader X Driver 410.57 Tue Sep 18 23:30:38 CDT 2018
[ 8.303] (II) NVIDIA Unified Driver for all Supported NVIDIA GPUs
[ 8.303] xf86EnableIOPorts: failed to set IOPL for I/O (Operation not permitted)
[ 8.303] (II) systemd-logind: releasing fd for 226:0
[ 8.305] (II) Loading sub module "fb"
[ 8.305] (II) LoadModule: "fb"
[ 8.305] (II) Loading /usr/lib/xorg/modules/libfb.so
[ 8.306] (II) Module fb: vendor="X.Org Foundation"
[ 8.306] compiled for 1.20.1, module version = 1.0.0
[ 8.306] ABI class: X.Org ANSI C Emulation, version 0.4
[ 8.306] (II) Loading sub module "wfb"
[ 8.306] (II) LoadModule: "wfb"
[ 8.306] (II) Loading /usr/lib/xorg/modules/libwfb.so
[ 8.306] (II) Module wfb: vendor="X.Org Foundation"
[ 8.306] compiled for 1.20.1, module version = 1.0.0
[ 8.306] ABI class: X.Org ANSI C Emulation, version 0.4
[ 8.307] (II) Loading sub module "ramdac"
[ 8.307] (II) LoadModule: "ramdac"
[ 8.307] (II) Module "ramdac" already built-in
[ 8.311] (EE) NVIDIA: Failed to initialize the NVIDIA kernel module. Please see the
[ 8.311] (EE) NVIDIA: system's kernel log for additional error messages and
[ 8.311] (EE) NVIDIA: consult the NVIDIA README for details.
[ 8.311] (EE) No devices detected.
[ 8.311] (EE)
Fatal server error:
Also, are you sure this is caused by the testing/nvidia package? Can you try the extra/nvidia-dkms package?
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