2021-01-30 ☼ linux
I purchased a Dell XPS 9300 Developer Edition laptop in August 2020. It shipped with Ubuntu 20.04, but I replaced it with Arch Linux. This was a return to Linux for me since switching all my machines to MacOS in 2005.
Overall the quality of the machine has been superb. I got the 4k screen and HiDPI support in GNOME has been great. The bezel-less design also makes it feel like a laptop from the future.
The only issue I’ve had so far has been the occasional wifi connection drops. The XPS 9300 — and it’s successor the 9310 — both ship with the Killer Wifi AX1650 card. With a Linux 5.4+ kernel, the card works out of the box utilizing
iwlwifi. While on battery power, though, I would experience a connection drop every few hours. The only thing that would fix it would be to either 1) plug in a power cable or 2) toggle the connect in NetworkManager. Neither have been ideal and I have always suspected some sort of power save setting. I think the combination of having older Airport Extreme routers that don’t support power saving and athe Killer Wifi card was the source of the problems.
I tried various fixes from forums around the web, but nothing seemed to help. There were also a lot of other recommendations for disabling hardware encryption and some antenna aggregation tweaks that I was hoping to avoid if possible. Based on user reports, these settings could help connection stability, but at the cost of wifi performance.
Thanks to the Arch Linux Wiki, I noticed a setting I had not yet tried. Here is what my
/etc/modprobe.d/iwlwifi.conf file looks like:
options iwlwifi power_save=0 d0i3_disable=0 uapsd_disable=0
options iwlmvm power_scheme=3
If this file doesn’t exist, go ahead and create it. The missing line for me was line 2. There are two variants for
iwlwifi cards, and you can find out which variant with this command:
lsmod | grep '^iwl.vm'
This will return either
iwldvm. For me it was the former. If yours is the latter, replace line 2 with:
options iwldvm force_cam=0
And that’s it! You’ll want to reboot your system after you make these changes, but hopefully that fixes your connection drops without sacrificing your wifi performance.