Why is the image grainy?


#1

Toshiba Satellite with UGA-2K-A to external 24" 1080p LCD and everything (esp images) are grainy. Windows 7-64bit shows the resolution at 1920x1080. Side by side comparisons are “dramatically bad”.


#2

Hi Matt,

Happy new year. Thanks for your patience! We’ll be able to help.

On stable images, quality with a USB graphics adapter should be identical to any inbuilt graphics adapter (and perhaps better on some laptops, as the USB graphics adapter will often support higher resolution modes than the in-built GPU).

So if you’re seeing graininess, the 3 most likely reasons are:

  1. If the resolution is not set to the native resolution of the monitor (or the adapter isn’t capable of that resolution), the monitor has to scale the image. Most people would describe that as a “squished” image, but some would call it grainy. (You’ve already ruled this out in your case)

  2. If it’s grainy just for a split second and then gets clear, that’s DisplayLink’s “optimize for video” feature, which uses interlacing for short stretches, to keep up with framerate. Try turning off “Optimize for Video” in the DisplayLink tray applet (although it will still do it when it falls significantly behind).

  3. If it’s a graininess (almost waviness) across the entire screen that remains even when nothing on the screen is changing, that’s most often because the USB port the adapter is plugged into is not supplying USB 2.0’s full 500mA of power. The adapter is in a brownout condition. Usually that’s because the adapter is being connected through an unpowered hub. Try connecting the adapter directly to the PC and/or through a wall-powered USB hub to confirm if it eliminates the graininess.

And if it’s none of those three, there’s a chance it’s a bad unit. Just email support@plugable.com with your Amazon order # and unit serial #, and we’d be happy to get you fixed up.

Hope that helps. Thanks again!
Bernie


#3

Thanks. This was good information. I pulled another monitor and did not see the issue. I had to go through the settings on the TV and found the issue eventually, though quite peculiar. A perfect picture now. Super product.


#4

Wonderful! Glad to have you up and running!


#5