XPS 8960, WiFi connection randomly resets

<Moved out of XPS Laptops and into XPS Desktops. DELL-Admin>

Hi,

Anyone have this problem / was able to resolve it? Dell XPS 8960 (pulled 8GB RAM and placed 16GB x 2; added additional M.2 SSD drive).

WiFi error message appears randomly:

This site can’t be reached

The connection was reset. Try: Checking the connection Checking the proxy and the firewall Running Windows Network Diagnostics ERR_CONNECTION_RESET

Does not happen to any other computer, including the old Dell desktop it's replacing. Does not happen with Ethernet connection. So far have tried:

Different browsers (same error)

Dell first reinstalled Windows and updated network drivers

Sent computer back to Dell, they replaced wifi card (Killer)

Dell sent tech and replaced motherboard

Reinstalled Windows and updated network drivers after that again

No luck.

It does not seem to happen when I use a Linux USB stick.

With the amount of time I spent on this, would have been cheaper to toss the computer and buy a different one, but here I am.