Resolution of secondary monitor changes

Geoff Lewis · 10-31-2014, 09:40 AM

We are using a primary monitor with a resolution of 1920 x 1080.
For eyesight reasons, some users change the resolution of the primary monitor to 1024x748. In this case the resolution of the DTU-1031 (secondary monitor) switches to 1024x768 on pressing the "Apply" button in the Screen Resolution dialog (it should stay at 1280x800).

With a primary monitor that has a resolution near 1280x800, the problem doesn’t occur.

We are using DisplayLink_7.6M2 (7.6.56).
For information, it seems that with v7.3.49, we did not have this problem.

Wim · 10-31-2014, 10:16 AM

I assume you are in mirror mode? If so, both displays will need to be set at the same resolution. The shared resolution will depend on the advertised resolution of the 2 screens, and the best resolution that is available for both displays to support.

Wim

Geoff Lewis · 11-04-2014, 01:18 PM

Thanks for your reply Wim.
On further investigation I decided that our user had misunderstood the situation. The displays were in fact not in mirror mode but as desktop extensions.
What happened was that sometimes when the resolution of the primary monitor was reduced the desktop background picture would be reduced in size on one or more of the other monitors in use. It wasn't the resolution that was changing, only the amount of the screen covered by the background picture on the secondary display(s).

I found that this also happened when DisplayLink was not installed and have therefore informed our customer that it is a Windows bug.

Thanks again

Geoff

Wim · 11-04-2014, 01:36 PM

Yes - that's correct. The background wallpaper will only be the same size as the primary. This means that if the extended screen is at a higher resolution, the background will have black borders.

Wim

10-31-2014, 09:40 AM	#1
Geoff Lewis Junior Member Join Date: Oct 2014 Posts: 6	Resolution of secondary monitor changes We are using a primary monitor with a resolution of 1920 x 1080. For eyesight reasons, some users change the resolution of the primary monitor to 1024x748. In this case the resolution of the DTU-1031 (secondary monitor) switches to 1024x768 on pressing the "Apply" button in the Screen Resolution dialog (it should stay at 1280x800). With a primary monitor that has a resolution near 1280x800, the problem doesn’t occur. We are using DisplayLink_7.6M2 (7.6.56). For information, it seems that with v7.3.49, we did not have this problem.

10-31-2014, 10:16 AM	#2
Wim Senior Member Join Date: Feb 2009 Posts: 1,561	I assume you are in mirror mode? If so, both displays will need to be set at the same resolution. The shared resolution will depend on the advertised resolution of the 2 screens, and the best resolution that is available for both displays to support. Wim

11-04-2014, 01:18 PM	#3
Geoff Lewis Junior Member Join Date: Oct 2014 Posts: 6	Thanks for your reply Wim. On further investigation I decided that our user had misunderstood the situation. The displays were in fact not in mirror mode but as desktop extensions. What happened was that sometimes when the resolution of the primary monitor was reduced the desktop background picture would be reduced in size on one or more of the other monitors in use. It wasn't the resolution that was changing, only the amount of the screen covered by the background picture on the secondary display(s). I found that this also happened when DisplayLink was not installed and have therefore informed our customer that it is a Windows bug. Thanks again Geoff

11-04-2014, 01:36 PM	#4
Wim Senior Member Join Date: Feb 2009 Posts: 1,561	Yes - that's correct. The background wallpaper will only be the same size as the primary. This means that if the extended screen is at a higher resolution, the background will have black borders. Wim