It’s a lenovo ideapad Z710 laptop with 12MB memory. Have been running Antergos on it for at least 6 months as replacement for Windows 10 very successfully. This has been going on for about 3 weeks but this is the first chance to try to get it sorted.
Running Linux 4.15.13-1-ARCH and same thing happens with the LTS version. Haven’t changed the hardware, so my theory is that something has come through in terms of a change which has not been handled well by this combination of hardware.
System seems to boot normally, then Chromium browser works fine, terminal works fine, all updates working do fully up to date.
Then after a period of time perhaps half an hour to an hour but always when I’m not there, I’ll come back and there’s the blank screen, no error messages, and a horizontal underline cursor in the top left corner.