Question Dual displays using display ports: one suddenly gets "no signal detected", other repeatedly flashes on and off.

[kevalin]

Hi, All,

Here are my specs:

Intel Core I-7 4790
Gigabyte GA Z97X Gaming 7 Motherboard
G.Skill DDR3 1600 CL 10 Memory, 16 GB
Gigabyte GeForce GTX 1600 6GB Mini OC GPU
Rosewill 500W 80+Bronze PSU
Four or five (can't remember off hand) SSD's and Hard Drives, running, variously, Windows 7 and Windows 8.1
2 Asus PA278QV 27" Monitors, each plugged into a display port.

Until tonight, the computer ran perfectly well, other than Windows 8 being it's usual annoying self. Tonight, however, when I went to wake up my computer, my monitors began acting very strangely.

What the computer considers the "secondary" monitor suddenly is getting the "no signal detected" message, and the "main" monitor flashes on and off.

Restarting the computer doesn't help. When I plug any one monitor into any of the GPU's three display ports, they work fine. Try plugging them both in at the same time, however, and the trouble begins.

I've been using these monitors for almost three months with no problems whatsoever.

Having read a few comments about similar issues, my first inclination is to replace my cheap old PSU, which I bought in 2019. But if anyone has any other suggestions, because this is my work computer, and what a pain in the butt dismantling it would be right now, I would greatly appreciate it.

 

[egda23]

Tried other cables? Checked with each one ?
Tried the HDMI connector ?

 

[kevalin]

Yes, yes, and yes.

Same results.

 

[egda23]

As I understand your graphic card neeeds only 1 power connector and your PSU has seemingly 2 PCI-Express power connectors.
Have you tried the other one ?

 

[kevalin]

Ahhh... that sound of minor dismantlement... but no, I haven't.

I will do so and see if it works--and thanks for the suggestion.

I went ahead and ordered a new PSU (Corsair CMX 650W, because it cost a whole $5.40 more than the 550 W). it's scheduled to get here later today, but I'd rather be able to send it back without opening it, if at all possible. So, hopefully the issue will turn out to be something this simple.