Wifi dies unexpectedly

[stukem]

I bought a laptop (spec below) that contained an Intel AX200 wifi card. I installed Ubuntu 18.04. Intel do not publish drivers for this device on linux kernel 4. I eventually managed to find an Intel backport driver for linux kernel 4 and got the wifi working.

There are 6 people in our office and we average 30 mbps upload/download on the wifi. After a few days my wifi crashed to almost zero bandwidth (about 0.1 mbps). No amount of restarting the laptop or wifi card helped. No one else in the office was effected.

I decided it could be a driver issue and went ahead and bought a new wifi card - an Intel 9260, which has official drivers for linux kernel 4. I installed the card yesterday, purged the old drivers, and it worked right out of the box. I had no problems all day. This morning, the wifi on the laptop has crashed to zero again. No other users are effected. The wifi card has power management turned off. Again, no amount of restarting the laptop, interface or networking is helping.

Can anyone suggest an explanation for this? I think I'm going to have to return the laptop.

Chassis & Display
Cosmos Series: 15.6" Matte Full HD IPS 60Hz 45% NTSC LED Widescreen (1920x1080)
Processor (CPU)
Intel® Core™ i7 Six Core Processor 9750H (2.6GHz, 4.5GHz Turbo)
Memory (RAM)
16GB Corsair 2133MHz SODIMM DDR4 (1 x 16GB)
Graphics Card
NVIDIA® GeForce® GTX 1050 - 3.0GB GDDR5 Video RAM - DirectX® 12.1
1st Storage Drive
500GB SEAGATE BARRACUDA 2.5" SSD, (upto 560MB/sR | 535MB/sW)
Memory Card Reader
Integrated 6 in 1 Card Reader (SD /Mini SD/ SDHC / SDXC / MMC / RSMMC)
AC Adaptor
1 x 120W AC Adaptor
Power Cable
1 x 1 Metre Cloverleaf UK Power Cable
Battery
Cosmos VIII Series 4 Cell Lithium Ion Battery
Thermal Paste
STANDARD THERMAL PASTE FOR SUFFICIENT COOLING
Sound Card
2 Channel High Def. Audio + SoundBlaster™ Cinema
Bluetooth & Wireless
GIGABIT LAN & WIRELESS INTEL® Wi-Fi 6 AX200 (2.4 Gbps) + BT 5.0

*Replaced with Intel 9260. AX200 has no drivers on Linux kernel 4 (Ubuntu 18). Intel 9260 works out of the box.
USB/Thunderbolt Options
1 x USB 3.1 PORT (Type C) + 2 x USB 3.0 PORTS + 1 x USB 2.0 PORT

 

[stukem]

I tested the wifi again this morning and it still wasn't working. I took the back off the laptop to check the wifi card connections, which appeared fine. I gave them a good push down anyway and sure enough on reboot the wifi was working. So I'm pretty sure the underlying problem here is the connections to the wifi card.

I will message support, but does anyone have advice on how to manage faulty connections to the device? I'm guessing some sort of non-permanent glue might help?

 

[markh]

why not upgrade to 19.04 / 19.10 with a version 5 kernel? then you would have the drivers for the newer wifi card

 

[stukem]

Hi,

I did actually upgrade to kernel 5. I couldn't then boot into the desktop, presumably because my Nvidia drivers were not longer working. I couldn't get any networking working in safe mode and eventually gave up on that route and returned to kernel 4. I was also not keen on moving to Ubuntu 19 in any case as its not a LTS version.

I suspected the AX200 and drivers were the problem. As mentioned, I have now confirmed, I think, that the issue is in fact faulty aux wire connections to the wifi card. Therefore the driver compatibility is no longer an issue - the backport driver was fine, its just the connections keep working loose.