Feedback on the Dell Latitude 5591 - Frozen when shutdown

Basically, Dell Latitude 5591 is not compatible with Ubuntu at all! (Neither 16.04 nor 18.04).

With Ubuntu 16.04:

1. The installation program does not recognize Wi-Fi
2. After installation, click the Restart button, the system freezes
3. Shutdown the machine by force. Reboot it. The system is not stable, and freeze randomly

With Ubuntu 18.04

1. The Wifi is recognize
2. After installation, click the Restart button, the system freezes
3. Shutdown the machine by force. Reboot it. The system is not stable and freezes randomly.
4. Ubuntu could not shut down or reboot normally (freeze)

I turn on shutdown log, it shows as:

[***] A stop job is running for session 2 of user <my_user_name> (22s/ 1min 30s) [72.335933] [TTM] Buffer eviction failed
[***] A stop job is running for session 2 of user <my_user_name> (37s / 1min 30s) [ 87.334695] nouveau 0000:01:00.0: DRM: failed to idle channel 0 [DRM]
................. (similar info) Watchdog detected hard LOCKUP on cpu 8
......

I've tried to upgrade Kernal version to 4.19, the issue stll could not be solved.

I guess this may be related with display card driver after Googled related information.

Really need help.

I brought this computer because it is listed in the certified list. But ... very disappointed. If this could not be solved in near future, I probably need to refund this laptop.

I brought DELL Latitude in Australia. The Dell Australia does not provide Ubuntu pre-installed version and I can't find anywhere to download the Dell version of Ubuntu for this machine.

I know the certified list said it may require special Dell version ubuntu (16.04). Standard Ubuntu may not work. But now Ubuntu 18.04 has been released. I thought it should compatible with this laptop.

Overall, for potential buyers, DO NOT buy Dell Latitude 5591 for Ubuntu. It is NOT working on Ubuntu 16.04 or 18.04!!!