My laptop can hibernate and wake up fine after a short time, using either sudo pm-hibernate or the Hibernate option from the system menu (which I enabled after the pm-hibernate test worked). But if I leave it hibernated overnight, it doesn't wake up properly: the screen flashes with the manufacturer's name, then goes blank and stays like that, with the power light on and the fan working. The only thing it reacts to is a hard restart with the power button.
I don't think it's just the screen not working - I tried logging in blind and running a command to make a sound, and it doesn't work.
Has anyone run into a similar issue, or does anyone know what could be causing it or how to debug it?
Xubuntu 15.10, 4.2.0-27-generic #32-Ubuntu SMP x86_64 GNU/Linux.
The laptop appears to be an ASI Compal VAW70 - I bought it from ZaReason as UltraLap 440, but it says VAW70 on the sticker on the bottom, and it looks the same. It has a 1T Crucial SSD, if that's relevant at all.
