monitor problems

[jamesbowers]

I have a new 2018 Mac Mini (running OS 10.14.2) which is connected to a LG 24UD58 monitor via a USB3 to DisplayPort cable.
When I shut down the Mac and then try to start it up again, the monitor is blank and does not appear to be receiving a signal from the Mac. I had the same problem when using another monitor (my old Dell U2312HM) using the DisplayPort cable.
Can you help me!
Thanks.

 

[Fishrrman]

When you shut down the Mac, are you leaving the display powered on?

What happens if you do this:
1. Shut down Mac
2. Power off display
3. Power on Mac
4. Power on display

??

 

[ajaan]

Same problem with a different monitor. It seems to depend on the brand of monitor and going though USB-c. I've tested four monitors on my mini. When I connect HDMI - HDMI there is no problem. Some monitors wake up with USB-c - DP, some don't. I have to switch my Samsung on and off when waking the mini up. The Hanns G connected via HMDI wakes up automatically.