linux. How to track what is causing the system to freeze?

Question

linux

On the laptop Dell Latitude e5470 were Ubutnu 18.04, 20.04, Mint 20. Sometimes it freezes tightly. In general, they do not react to anything except turning off by pressing the power button. Sometimes you have to reboot several times, because. hangs up a couple of minutes after loading and login. There is an assumption that this only occurs when a monitor is connected via hdmi, but this is not accurate. journalctl -xe does not contain any errors after loading

Answer 1

Try to look at the errors through the dmesg -T command or in /var/log

Answer 2

There was a similar problem on xubuntu 18.04 on acer (it is not known what kind of pieces of iron they shove there, but there are always some problems with them) when using an integrated video card. I forced the use of a discrete one - the machine stopped hanging tightly, but sometimes it hung for a second. Gone with some update.
I observed similar freezes on CentOS 7 on one stationary machine. Exposed policy "performane" through tuned - had no effect. But the bug seems to have also been fixed with some kind of update.

Answer 3

You can try using kdump. It seems like pressing a combination of buttons will reset the dump and then you can study it. Most likely a hardware problem. If you can, clean the memory contacts with an eraser - there are no more contacts in the lapta.