Mac OS 15.5.5 eGPU only - Monitor might be the cause of most issues
Monitor: Shared between windows PC (DVI) and Mac Mini (HDMI to eGPU).
Solution to most of my problems:
Before powering the mac mini (or wake from monitor sleep/standby), select the HDMI input in the monitor (ASUS PB0278), then quickly start the mac mini (or wake up). This does not work with Display Port.
My conclusion is that my screen is not receiving/sending the right signal to the eGPU via DP when the screen is off, and the eGPU does not manage to start working properly. However with HDMI it works, BUT the screen needs to be ON (not standby) first with the right HDMI input from the eGPU.
Here you have some details of all the configurations/tests I had:
Boot: Sometimes boots, sometimes not. Freeze during startup, login screen is not even reached, caps lock not working. I have to shutdown and try again.
Wake from sleep: Most times does not work. Have to unplug eGPU TB3 cable and reattach, this sometimes fixes the issue.
Wake screen only (mac was not sleeping): Same as before.
eGPU and Mac Mini HDMI:
Boot: Always works. Combined with SwitchResX and some scripts to disable the mac mini hdmi output on startup/wake is quite usable, but I need to switch from HDMI to DP every time since the HDMI output is detected first and the screen remains there.
Wake from sleep: The hammerspoon script combined with SwitchResX works quite well, although sometimes the eGPU connection is lost and I need to disconnect/connect the TB3 cable.
I decided to use a dummy HDMI plug to replace the Mac Mini -> HDMI -> Monitor connection, so I would not have to switch all the time inputs in the monitor. However since the eGPU sometimes is lost (during monitor sleep, not even mac mini sleeping!), then I am completely blank. I had to reconnect the TB3 eGPU cable.
So after doing all these tests I realized that the screen going to sleep was very often the problem. Somehow the eGPU is not able to detect the screen and then no matter what I do I have to plug/unplug the TB3 cable. However I found a way that it works ALWAYS:
o my conclusion is that my monitor is not receiving/sending the right signal to the eGPU via DP when the screen is off, and the eGPU does not manage to start working properly. However with HDMI it works, BUT the screen needs to be on first.
EDIT: Disconnecting the TB3 before start and connecting it after a few seconds works (as most of you probably know), but I don't like to put stress on the connector each time I start/wake up my computer. My enclosure is under the desk so powering on/off each time is annoying as well. Thus I find to be better approach to select the HDMI input in my screen each time instead.