Hi Michael, thanks for posting! Sorry to hear of the sluggish behavior you experienced with our adapter and I will be happy to help!
Thank you for the description of the behavior and the steps you took to mitigate the behavior. However, I would not expect this behavior and it could be a number of things that could contribute to the behavior. I would be happy to dive into some log files to see if they can tell us what could be happening, if you are interested. To help me do so, please download and run our diagnostic utility PlugDebug --> http://plugable.com/support/plugdebug with everything connected. Please send us the file that is created on your Desktop to our direct support email at firstname.lastname@example.org with ‘Ticket Number 154274’ in the subject line so we can match everything up. We’ll examine the logs to determine what else could be done or what could have been causing this behavior.
Regarding being able to tell if the adapters are using a USB 3.0 or USB 2.0 port, it depends entirely on the system. A common visual indicator that manufacturers use is to color the plastic parts inside of the USB 3.0 port blue and this matches with the blue plastic that is on the USB connector end of our adapter’s cable. Another indicator that some systems use is to put the USB 2.0 or USB 3.0 symbol next to the USB port itself. Please see this image --> https://nikeagent.custhelp.com/rnt/rn… that quickly illustrated the USB 3.0 and USB 2.0 symbols. If you are unable to determine which ports are USB 3.0 or USB 2.0 on your Dell Precision laptop, please just let me know the specific model number and I will be happy to look up specifications online to help determine this.