External Display using USB-C to HDMI // Silicon Motion Graphics (SMI)

[xxwitcher]

IMPORTANT!

This guide is specific for HDMI to USB-C adapters that use Silicon Motion drivers.

If your adapter is using base DisplayLink just run sudo pacman -S displaylink, reboot and it should work. If it doesn't - join the Discord and ask for help.

Adapters with DP alt mode (most of them are like that) will not work no matter what you do. DP Alt mode has not yet been reverse engineered (thanks Apple).

When browsing for an adapter you're looking for something like this in the description:
Compatibility: Driver installation is required. The UGA-HDMI-2S uses Silicon Motion (SMI) graphics software.

CHECK THE REFRESH RATE SUPPORT BEFORE YOU BUY AN ADAPTER!

Here's one I found on Amazon US that uses SMI Drivers

Another one for UK (the one I use)

You'll have an easier time if you search for M1 Air x2 HDMI adapters as that model has only 1 display supported via DP Alt mode so anything that has 2 ports will be DisplayLink or SMI.

Let's begin

git clone https://github.com/xxwitcher/witchers-tweaks.git ~/witchers-tweaks
~/witchers-tweaks/install.sh

The install script comes along with some other tweaks and you can pick and choose. Head over to the repo if you want to learn more about those.

smidriver is the applicable option for the monitors. It automatically detects your monitors (assuming they're already plugged in) and will allow you to configure them at the end.
At the moment if you choose to turn off the built-in display at first glance nothing changes but once you save and exit the display will turn off. I'll patch this in future updates.

In the future if you want to reconfigure the monitors using this tool you can pass the --monitors command:

./install.sh --monitors

If the monitor(s) does not turn on immediately then reboot and it should work fine.

HELP! It still doesn't work!

Answer these questions:

• Did you try to turn it off and on again?
• Is your adapter Display Link or Silicon Motion?
• Are you sure?

If you answer "yes" to all of these and it's still not working - get in the Discord