Yeah, users have been reporting problems with Killer-Networking cards since like 2010. Apparently, the Aliens love them. Maybe Rivet got assimilated or something (not sure).

I have an Aurora-R6. I don't use the WiFi, but do use it's on-board Killer Networks e2400 Wired Gigabit Ethernet. I had a serious driver-issue when it was new, but I did as below and it's been fine since.

Usually, Killer-Networking cards are just Broadcom-cards. Now that Intel bought Rivet-Networks, not really sure what chipset they use.

Anyway, I tend to fix it like this (and suggest this):

Uninstall all Killer-Networking (heavy driver-suite) non-sense . Then, delete the card(s) from Device-Manager. Reboot and let Windows Plug-and-Pray . It will re-detect and then just use the Microsoft WHQL (or Broadcom) drivers it tosses you. They are lean/fast and just work fast, stable, and with no packet-loss (which is all you really need ).

https://www.dell.com/community/XPS-Desktops/XPS-8930-Killer-E2400-Gigabit-Ethernet-stopped-working/m-p/8156140/highlight/true#M69383

If that doesn't help, you can try re-seating the little-baby card (and check that the antenna-wires are snapped-on properly).

If still not working, it might just be a bad card. They are mass-produced and inexpensive. For like $25, you can get another one and your problems go away.

Finally, these are stationary desktops. I know it's hard (and attics are hot) but running a real cat-6 cable to the room is usually worth the effort. Also, if you are doing any network, media server, or home theater ... a real wire has lots of dependable bandwidth . Save the WiFi for the laptops, phones, and tablets/iPads.