Slow internet download speeds when connected to USB2-E1000


I have an issue that is driving me crazy. I have fiber internet service that is 100mbps down, and use the USB2-E1000 to connect directly to the ZyXEL router. Until recently, i got this speed reliably as measured using speedtest. I recently noticed that it had slowed to 35-40mbps and got Centurylink involved. They plugged direct from a laptop into the same router and got 100+. My other PC’s on the LAN get 100+. So it seems it’s my connection. What can you suggest to help troubleshoot this?


Hi TB,

Thank you for posting your question.

Can you please tell me a few details about what is happening?

  1. What make and model of computer are you using the adapter with?
  2. When did you first start seeing the lower speeds?
  3. Are there any other adapters (like wifi) on the computer?




Thanks, David. Details:

  1. Lenovo X1 Carbon
  2. In the past couple of weeks, but no event triggered it that I noticed.
  3. Built in wifi, and a USB connection to the Lenovo USB hub.




Hi Todd,

Thanks for the information.

The reason I asked about whether it started recently is because the internet as a whole has been going slow for the last week or so because Microsoft rented about 30% of worldwide bandwidth for the Windows 10 rollout and it is slowing things down.

It is not usual for an adapter to start slowing down, usually if they are bad, they just fail altogether.

We have a troubleshooting tool that can help find out what is going on in situations like this. Please go to this page, and follow the instructions there:

It will create a zip file on your desk with logs and device driver information. Please send it directly to our support address at