Periodic Loss of Internet Intel AC 7260

Hello -

I have an annoying problem where my Internet connection is lost after working fine for many hours or 10's of minutes. By loss of Internet I mean that Windows tells me that I am connected to my WiFi router but the router isn't connected to the Internet. However, only my M4800 has lost connection. The other devices connected to the router (phones and tablets) are working just fine.

The only remedy that I've come up with to clear the issue is to re-boot. There may be a clue for one of you in the behavior when I try to re-boot. First off my M4800 is closed and in a Port Replication with stand. When I use Windows to shutdown things look quite normal until the very end. My monitors go blank but my power light doesn't go off. I have to hold the power button in order for the power light to go off. If I go through the same exercise, but not in response to the Internet problem, the computer shuts down normally.

My WiFi adapter is an Intel AC 7260 with the latest driver. I'm an old hardware engineer and usually like to blame the software for any problems but wondering if it's time to replace the AC 7260.

Thanks for looking - Bill