Hi Bill,
You may try to update the adapter's Boot Agent. The Boot Agent acts like the adapter's firmware. Updating it refreshes the adapter's controller and it may fix the issue. Please find the update procedure here - Intel® Boot Agent — How to Update Intel® Boot Agent
In case you still encounter the "Cable Unplugged" issue, if possible, use another system to test the network card and see if you encounter the same issue. Because it is possible that your network card is defective and needs a replacement. If you don't have other system, try to contact your place of purchase for assistance. You may contact us for live support - Contact Intel Customer Support
We look forward to your test results.
Sincerely,
Sandy