[W530] Freezes and Random Reboots. CPU or Motherboard?

[tamqra]

I got this error from Ubuntu 18.04 to the latest Ubuntu version.

Thinkpad W530 sometimes power down and restart when I use Intel Graphic Card.

I tried to find the cause, tried a bunch of Linux versions, only Fedora 19 Live, tried stress test tools, and the Thinkpad W530 didn't reboot.

It is not clear whether the cause is an Intel Graphic Driver compatibility error?
I can't afford to test.