Looks like you where right about the udev rules earlier, I ran a pacman command to find all untracked files in /usr and I found /usr/lib/udev/rules.d/50-remove-nvidia.rules was there. Contents:

# Automatically generated by EnvyControl

# Remove NVIDIA USB xHCI Host Controller devices, if present
ACTION=="add", SUBSYSTEM=="pci", ATTR{vendor}=="0x10de", ATTR{class}=="0x0c0330", ATTR{power/control}="auto", ATTR{remove}="1"

# Remove NVIDIA USB Type-C UCSI devices, if present
ACTION=="add", SUBSYSTEM=="pci", ATTR{vendor}=="0x10de", ATTR{class}=="0x0c8000", ATTR{power/control}="auto", ATTR{remove}="1"

# Remove NVIDIA Audio devices, if present
ACTION=="add", SUBSYSTEM=="pci", ATTR{vendor}=="0x10de", ATTR{class}=="0x040300", ATTR{power/control}="auto", ATTR{remove}="1"

# Remove NVIDIA VGA/3D controller devices
ACTION=="add", SUBSYSTEM=="pci", ATTR{vendor}=="0x10de", ATTR{class}=="0x03[0-9]*", ATTR{power/control}="auto", ATTR{remove}="1"

looks like EnvyControl left some extra files after uninstalling.
Personally, I think it’s pretty weird that it put runtime files in /usr/lib, if they where in /etc I would have found them quickly.
The GPU is back on the bus now and I can run optimus-manager to get my extra screen. Thank you for the help troubleshooting this issue.

dkms status doesn’t even list half of my DKMS modules for some reason

I don’t seem to have an -F on my dkms? when I ran that it without, it didn’t rebuild all the DKMS modules for some reason, just bbswitch and evdi

interesting, that did show the nvidia card in dmesg, still not in lspci though

[ 1110.598286] pci 0000:01:00.0: [10de:1ba1] type 00 class 0x030000
[ 1110.598301] pci 0000:01:00.0: reg 0x10: [mem 0xde000000-0xdeffffff]
[ 1110.598310] pci 0000:01:00.0: reg 0x14: [mem 0xc0000000-0xcfffffff 64bit pref]
[ 1110.598318] pci 0000:01:00.0: reg 0x1c: [mem 0xd0000000-0xd1ffffff 64bit pref]
[ 1110.598324] pci 0000:01:00.0: reg 0x24: [io  0xe000-0xe07f]
[ 1110.598330] pci 0000:01:00.0: reg 0x30: [mem 0xdf000000-0xdf07ffff pref]
[ 1110.599069] pci 0000:01:00.0: vgaarb: bridge control possible
[ 1110.599073] pci 0000:01:00.0: vgaarb: VGA device added: decodes=io+mem,owns=none,locks=none
[ 1110.599078] i915 0000:00:02.0: vgaarb: VGA decodes changed: olddecodes=io+mem,decodes=none:owns=io+mem
[ 1110.599125] pci 0000:01:00.1: [10de:10f0] type 00 class 0x040300
[ 1110.599135] pci 0000:01:00.1: reg 0x10: [mem 0xdf080000-0xdf083fff]
[ 1110.599327] pci 0000:01:00.0: BAR 1: assigned [mem 0xc0000000-0xcfffffff 64bit pref]
[ 1110.599335] pci 0000:01:00.0: BAR 3: assigned [mem 0xd0000000-0xd1ffffff 64bit pref]
[ 1110.599341] pci 0000:01:00.0: BAR 0: assigned [mem 0xde000000-0xdeffffff]
[ 1110.599344] pci 0000:01:00.0: BAR 6: assigned [mem 0xdf000000-0xdf07ffff pref]
[ 1110.599347] pci 0000:01:00.1: BAR 0: assigned [mem 0xdf080000-0xdf083fff]
[ 1110.599349] pci 0000:01:00.0: BAR 5: assigned [io  0xe000-0xe07f]
[ 1110.599384] pci 0000:01:00.1: extending delay after power-on from D3hot to 20 msec
[ 1110.599418] pci 0000:01:00.1: D0 power state depends on 0000:01:00.0
[ 1110.599509] snd_hda_intel 0000:01:00.1: enabling device (0000 -> 0002)
[ 1110.599624] snd_hda_intel 0000:01:00.1: Disabling MSI
[ 1110.599630] snd_hda_intel 0000:01:00.1: Handle vga_switcheroo audio client
[ 1110.603829] i915 0000:00:02.0: vgaarb: VGA decodes changed: olddecodes=none,decodes=io+mem:owns=io+mem
[ 1110.628268] input: HDA NVidia HDMI/DP,pcm=3 as /devices/pci0000:00/0000:00:01.0/0000:01:00.1/sound/card2/input18
[ 1110.628341] input: HDA NVidia HDMI/DP,pcm=7 as /devices/pci0000:00/0000:00:01.0/0000:01:00.1/sound/card2/input19
[ 1110.628403] input: HDA NVidia HDMI/DP,pcm=8 as /devices/pci0000:00/0000:00:01.0/0000:01:00.1/sound/card2/input20
[ 1110.628464] input: HDA NVidia HDMI/DP,pcm=9 as /devices/pci0000:00/0000:00:01.0/0000:01:00.1/sound/card2/input21

hmm, maybe downgrading nvidia-dkms might work? I’ll try that

yeah, they are a bit of a pain, but it’s a new one to me for the card to just disappear completely. It’s hard to do any troubleshooting when you can’t even access the card.

I had a look at /etc/udev, /etc/modprobe.d and /etc/modules-load.d, and don’t see anything related to nvidia. Are there any more udev or blacklist folders to look at?

It’s an MSI GE72MVR 7RG, what do mean version?
and it’s an integrated intel GPU.

ls: cannot access '/sys/bus/pci/devices/0000:01:00.0': No such file or directory
I also tried booting an archiso and the GPU appears there, there must be something wrong with my install.

It disappeared without me booting into windows, I booted windows to test after it was gone. But I did just try to force a hard shutdown on windows and disabled fastboot, but it’s still not appearing.