Personal computing discussed

Moderators: renee, morphine, SecretSquirrel

 
Yan
Gerbil XP
Topic Author
Posts: 349
Joined: Fri Dec 21, 2012 9:37 pm
Location: Ottawa

Dual monitor setup no longer working

Mon Jan 13, 2020 5:39 pm

I have two monitors side by side under Windows 7. I used to have an "extended" desktop using both monitors, but the right monitor no longer works that way.

Both monitors work if I "duplicate" the desktop on both monitors, but only the left monitor works when I try to use an extended desktop. Also, if I try to put the desktop only on the right monitor, the left monitor doesn't work at all (no image).

Since the right monitor does work if I duplicate the desktop, I don't think there's anything wrong with the monitor itself, the cable, the graphics card, etc. I've checked that the drivers and the software are up to date.

Any suggestions?
 
Yan
Gerbil XP
Topic Author
Posts: 349
Joined: Fri Dec 21, 2012 9:37 pm
Location: Ottawa

Re: Dual monitor setup no longer working

Tue Jan 14, 2020 8:22 am

Solved: it was a bad cable after all. I should remember to always check the cable!
 
just brew it!
Administrator
Posts: 54500
Joined: Tue Aug 20, 2002 10:51 pm
Location: Somewhere, having a beer

Re: Dual monitor setup no longer working

Tue Jan 14, 2020 11:00 am

But a bad cable should've prevented it from working in mirrored mode too! The cable doesn't "know" what's being displayed on the other monitor.

Are you sure the act of disconnecting and reconnecting the cable didn't force the system to re-detect the monitor, thereby fixing the issue? I would be inclined to try the old cable again and see what happens.
Nostalgia isn't what it used to be.
 
Yan
Gerbil XP
Topic Author
Posts: 349
Joined: Fri Dec 21, 2012 9:37 pm
Location: Ottawa

Re: Dual monitor setup no longer working

Tue Jan 14, 2020 7:20 pm

I had already tried disconnecting and reconnecting the cable, and it didn't solve the problem. This time, I also reversed the cable: the end that was connected to the monitor is now connected to the graphics card, and vice versa. This solved the problem.

So I think the cable is slightly defective and I "jiggled" it enough to make it work again.

I agree that a bad cable should have prevented the monitor from working at all. It's strange.
 
ludi
Lord High Gerbil
Posts: 8646
Joined: Fri Jun 21, 2002 10:47 pm
Location: Sunny Colorado front range

Re: Dual monitor setup no longer working

Tue Jan 14, 2020 10:02 pm

If this were Windows 10, another possibility for this scenario is that Windows performed an on-the-fly automatic update of the graphics driver, and failed to correctly detect the second monitor afterwards. Since you're in Windows 7, I would bet on a cable going bad.
Abacus Model 2.5 | Quad-Row FX with 256 Cherry Red Slider Beads | Applewood Frame | Water Cooling by Brita Filtration

Who is online

Users browsing this forum: No registered users and 1 guest
GZIP: On