MoroS,
Thank you for the script. You are right, the laptop is overheating. The log files are massive to be copied here. I am pasting the last lines.
The laptop powers off in 10 minutes, 16:18:51 up 10 min, 3 users, load average: 5.64, 3.52, 1.63
It doesn't appear to use swap. total used free shared buffers cached
Mem: 2884688 2779960 104728 75744 152388 1744208
-/+ buffers/cache: 883364 2001324
Swap: 2654204 4 2654200
The temperature, when it powers off, acpitz-virtual-0
Adapter: Virtual device
temp1: +84.0°C (crit = +86.0°C)
temp2: +66.0°C (crit = +85.0°C)
coretemp-isa-0000
Adapter: ISA adapter
Core 0: +84.0°C (high = +80.0°C, crit = +90.0°C)
Core 2: +87.0°C (high = +80.0°C, crit = +90.0°C)
Can't buy a new laptop yet, so I might have to use Gzip, rather than XZ. Actually, there is a newer laptop at home, but neither SparkyLinux (any Debian) or Xubuntu connects to WiFi.