One of two identical monitors won't detect - but was working today!

Spuderoony · 11 Dec 2021 at 18:38

Hi

I've been using two Iiyama G-MASTER GB3466WQSU-B1 34" UWQHD as a dual display setup since August 21. Was all going fine until this afternoon.

I set my computer to sleep mode, but then a few seconds later realised I needed something off it, so quickly activated it again. Only one monitor turned on. Literally nothing else changed in those few seconds. And I can't get the monitor back.

It turns on and displays the white Iiyama test screen, which quickly disappears and then says no signal detected and it goes from blue light on to red light standby.

I've tried reinstalling drivers, playing with power settings, playing with display configuration, nothing is working. Windows no longer sees one of the monitors. When I go in device manager or display settings it only sees 1 monitor there.

This has been driving me mad for a couple of hours. Please help!

t31os · 11 Dec 2021 at 19:36

Swap the cables over, change the port your're plugging into (on the PC side), try a different input port on the problem screen (HDMI or whatever), try another device, be it another PC, laptop or your TV box. If one screen consistently does not function changing all those possible variables then you have your answer.

Spuderoony · 11 Dec 2021 at 23:03

I have tried reseating the graphics and that seems to have worked. But one DP slot won't work still, but the other does.

Thanks for the tips, though.

EsaT · 12 Dec 2021 at 12:43

Next time try doing complete power cycling, meaning powering everything down for good duration with power cords disconnected from wall.
That should clean at least some possible error states to wake things up.

Spuderoony · 12 Dec 2021 at 13:53

Yeah, I did that as part of the reseating, may have helped.

Thanks!