Comment 36 for bug 1922334

A couple of other behaviours I have observed now that may be useful for figuring this one out:

1. When this monitor (Benq EX2780Q) goes to standby, it stops showing signs of life on the signal line. This manifests as it disappearing completely from the system, including the sound output and the display device. Must be a power saving feature. I have not seen this on other monitors I've owned, so I thought this may be a contributing factor. Still, this does not result in the "fail to wake" issue on the XPS 9560 and on my Windows desktop connected to another input, so I don't think it is the monitor's fault.

2. When 2 external monitors are connected (not my original post's use case), Benq EX2780Q and LG 24MP57, and I power cycle the Benq for it to wake up, the LG 24MP57 goes into a slow loop where it blanks for a second, comes back for about 20 seconds, blanks for a second, repeat. If I get lucky and everything boots up on first attempt, without power cycling the Benq, this does not happen - which is why I thought it may be related.