I have a UD-3900 connected to my Lenovo X1 Carbon Touch with an HP2511x monitor connected to the DVI port on the Hub. The X1 Carbon is running Windows 8.1 with the latest DisplayLink Manager Software is installed (7.5.52874.0). When connected to the HUB, the 2511x is configured to be my only display. As tests, I have also tried spanning the display across the laptop and external display and also disconnected the HUB entirely. In all cases, the screen saver now fails to start.
Thanks for getting in contact with us. I’d be more than happy to help you with your Plugable UD-3900. In order to better assist you, I’ll need a bit of additional information.
Could you please provide the logs produced by our tool Plugdebug, you can find it here and then send them to me at firstname.lastname@example.org.
Once we have those logs, we’ll start trying to figure out what exactly is going on with your setup.