Ran out of time to edit my post... Also, open Device Manager and on toolbar, click View>Show hidden devices. Now go through the entire list in Device Manager and look for any "Unknown" device(s). If you find any, right-click and Uninstall Device. Then click Action>Scan for hardware changes, and see if Killer reappears under Network Adapters.
XPS 8930.  Been working trouble-free.  Ethernet connect to my router.  WiFi works fine. The other day, the ethernet connection failed.  Tried multiple diagnostics, restarts, cables, etc---all the usual easy stuff had no impact. 1) The killer driver won't install, says "no compatible device" 2) The ethernet controller is no longer in device manager/network adapters list 3) I think there's been a HW failure 3) As I understand it, the ethernet in this machine is part of motherboard 4) Do i get a new ethernet card?  Any recommendations?
Killer E2400 Ethernet Controller status "not present", not in device manager 
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