Ok, so I want to preface this saying that this is the 2nd Z321QU monitor I have which is displaying the exact same issue. The first one was RMA'd and the replacement has worked now for a few months, just like the first.
When I turn the monitor on, the blue light turns on, but the monitor never boots. I see no splash screen. The backlight doesn't come on. Nothing.
After 10-20 minutes, the monitor will sometimes, if it so desires, finally turn on. Sometimes it doesn't though. I seem to have better luck with this if I leave the monitor completely disconnected from power for 20 minutes before plugging it back in. If the monitor does decide to boot, it will work great (as if nothing is wrong with it) until my computer goes to sleep or is shut off. Then the monitor will freeze and refuse to turn on until I disconnect power for an extended time again or it just randomly decides it wants to work.
The problem happens with and without G-Sync enabled.
I disabled the Deep Sleep option in the monitor settings, same problem.
The problem happens even when disconnected from power and no DP or HDMI cables are plugged in when I restore power.
I have never overclocked this monitor. I run it at max 2560x1440 @144hz
I run Windows 10 with an Nvidia 1080ti.
I don't want to spend $80 to ship that massive box back to Texas again (thanks Acer for making us pay our own RMA shipping). I don't see any new firmware online. I am at a loss as to what to do next, but this is an expensive monitor and I don't want to buy another one.