When 4 USB displays are connected, two default to 640 x 480

[chris_05828]

Here's a problem I'm having on my machine. I have 4 SIIG USB2.0 to VGA Pro External Video Card Display adapters (http://www.newegg.com/Product/Product.aspx?Item=N82E16815150177) (Chipset: DisplayLink DL-165) hooked up to my machine. With only three connected, everything works just fine - when I connect the 4th (it doesn't matter which three or which one I use as the 4th) two of the displays go down to 640 x 480 and cannot be changed without messing up ALL the displays (other displays with change resolution, all displays will rearrange, all icons and programs with rearrange across displays).

I have tried different USB ports (currently each display is connected to it's own USB channel on the mainboard), I've tried uninstalling/reinstalling, I've gone through all the troubleshooting steps - and nothing will enable me to make this work.

DisplayLink Core Software (7.7.59503.0)
DisplayLink Graphics (7.7.59586.0)


Here's my configuration:

Acer 1920 x 1080 - connected to internal video card
Acer 1920 x 1080 - USB
Dell 1280 x 1024 - USB
Dell 1280 x 1024 - USB (Stuck in 640 x 480)
Dell 1280 x 1024 - USB (Stuck in 640 x 480)


I've attached the support file to this post.

[Wim]

I suspect this might be something to do with Windows or the graphics card. There is a known problem in Windows when the desktop exceeds 8192 pixels:

http://support.microsoft.com/kb/2724530/en-gb?wa=wsignin1.0

I also wonder if it could be a limitation of the NVIDIA graphics card unable to compsite this many pixels, so restricting the 5th display to 640x480 and reducing the resolution of the 4th display to achieve this.

I see you are already in basic mode, rather than aero glass, which is a sign that the graphics card has already turned off aero to be able to support the current number of displays.

If you reduce the resolution of the ASUS monitors, do the Dells start to work at the right resolution? That would be an indication you are hitting the upper bounds of the graphics card.

Wim

[chris_05828]

The desktop doesn't exceed 8192 pixels. The three monitors on top running at their resolution would make it 2048 pixels wide. The two monitors on the bottom would make the desktop 2160 pixels wide. Both on top of eahother would make the height 3200 pixels tall. Even laid out end-to-end the max desktop resolution would be 4208 pixels wide.

I have Aero turned off, and haven't tried turning it on.

The only way to get all the dell monitors working correctly, is to disconnect the one Acer 1080p monitor that's hooked up through USB.

I have attached a picture of the current setup - Monitor #2 and #3 are the ones that do not display correctly, unless monitor 5 is disconnected. Monitor #4 is completely unaffected by everything.



I also wonder if it could be a limitation of the NVIDIA graphics card unable to compsite this many pixels, so restricting the 5th display to 640x480 and reducing the resolution of the 4th display to achieve this.

I'm kind of curious about this, can you explain further? I thought the video was/is being handled by these USB adapters, and no the video card?

[Wim]

The graphics card is used by DisplayLink to help composite the desktop and enable us to support 3D effects, so we are reliant on the graphics card being able to support the number of pixels you are asking of it. I suspect the video card is at it's limit in this system, which is why the resolution is reduced to 640x480.

Wim

[chris_05828]

So pretty much, I spent almost $200 on useless adapters?