I wanted to print something from Arch, so I needed to install print-manager. It wouldn't work because of the mirrors returning a 404, so I just updated using "sudo pacman -Syu", and then installing print-manager worked.

Well when I rebooted my computer, everything went normal until the moment when the GUI is supposed to pop up, instead my monitors just show "Input Not Supported" and that's it.

I tried appending "init=/bin/bash" to Arch Linux in the GRUB menu to get into the command line or whatever, which worked, but then my keyboard didn't work. I couldn't type anything. I tried with multiple keyboards.

What can I do? I'm new to Linux, so I'm not sure what else I can try to revert the update I did. I really don't want to lose the stuff I've got on there

That and arch linux kinda don't go together.

Does the journal show anything? Look at man journalctl. If you can't boot to a working machine, then boot with the install media and chroot in.
man chroot

What kind of video hardware do you have? What kernel modules are loaded? The latest kernel and nvidia are a problem. (What's new).
Are you using X or wayland? What DE or WM are you using? Are you using a display manager?

If you are new to arch and linux, you are going to have a real hard time with this.

Here is what I can give you from what you have posted
https://wiki.archlinux.org/title/Xorg
https://wiki.archlinux.org/title/Wayland
https://wiki.archlinux.org/title/Systemd/Journal
https://wiki.archlinux.org/title/Chroot
https://wiki.archlinux.org/title/NVIDIA
https://wiki.archlinux.org/title/GRUB
https://wiki.archlinux.org/title/Kernel_mode_setting
https://wiki.archlinux.org/title/Kernel_parameters
https://wiki.archlinux.org/title/Display_manager

1 members found this post helpful.

Turns out it's my monitors?

I decided to try and install EndeavourOS on a separate drive and I once again got the "input not supported" message on my monitors. I then tried to install Fedora and I just got a black screen, which made me start to wonder if it's something other than Arch.

I decided to plug my PC into my TV via HDMI and I was able to boot into the original Arch drive.

So... why would my monitors decide to stop working with Linux randomly after I update my Arch?

Turns out it's something to do with my monitors?

I decided to try and install EndeavourOS on a separate drive and I got the same error on both monitors: "Input not supported". I then tried to install Fedora and I just got a black screen... so it made me think that it wasn't something with Arch. I then plugged my PC into my TV instead and I was able to boot into the original Arch drive...

What would make my monitors just stop working with Linux? Fedora, Arch? Everything was working just fine for months before.

Maybe try Ubuntu LTS or Debian stable instead?
I don't mean to be facetious, but if you can't even do very basic technical troubleshooting for your problem you should stick to something that is more likely to Just Work out of the box.

Solved my issue.

For anyone who may be struggling with something similar, here's the fix:

Turned out it was the Nvidia drivers. I booted into my Arch machine using the kernel parameter "systemd.unit=multi-user.target".

Then I uninstalled the Nvidia drivers (both nvidia and nvidia-utils) and then installed Nouveau drivers using the Nouveau Arch wiki and I was able boot right in.