Comment 25 for bug 1561902

Sounds more and more odd. Maybe things are related on how long the system is powered on. It has been a while, but I had that once. Random freezes but rather shortly after cold boot. Though that was a desktop and back then it was the connectors of the power supply not all fitted firmly. So depending on heating up the connection it would handle higher currents better or worse.

On the other hand you wrote that on Xenial this happened after one hour and immediately after. And by that time things should be warmed up enough... The problem of course is that without a repeatable method to trigger the problem or by luck get some error message, this will be near impossible to track down. The only thing I can think of is to try to remember whether there could be a pattern in what is being done primarily when lockups happen.