I've searched endlessly on these forums and on Google. I've come close to the answer where other users are having similar issues, but I still cannot come to a conclusion other than: "It's a bug."
I'm currently running Ubuntu 15.10 on my old 5560G Acer Aspire laptop and considering the laptop is quite old now, it runs like a dream. However, I have a problem with powering off the device when shutting down and restarting.
When I power down the device, however which way I choose to power it down- be it from terminal using the "force" shutdown commands- the system freezes and becomes unresponsive to key commands or anything. I have to force-power down the machine by holding the power off button. CTRL + ALT + Del also doesn't do anything. Auto power-off when the battery is low sees the same issue. Restarting works in that it successfully leaves the OS and posts to the BIOS but when grub should be loaded, it freezes and doesn't load Ubuntu. I'm not sure if this issue is related in some way with the shutdown fault behaviour. Suspend mode and closing the lid works flawlessly.
Something to note - The shutdown behaviour appears to power-down the drives as the hard drive and disk drive make a clicking sound when they're shut off, and the CPU fan resumes it's default speed (like it would in the BIOS) but this is where the system freezes. This leads me to believe it may be a low-level issues to do with communication between the OS and BIOS, though Windows didn't seem to have this issue.
- Using apci=force and other commands by modifying the grub config
- Shutting down using force commands from terminal
- Updating/downgrading BIOS firmware
- Freshly re-installing Ubuntu
- Turning off quiet splash and searching logs to observe any foul
behaviour that may prevent the machine from powering off completely.
From what I can tell, nothing out of the ordinary. The last message
before the machine freezes is
[ OK ] Reached Target Shutdown
- Unmounting Samba drives and other possibly conflicting drives
Basically, I've come to a dead-end in my search. I do think it is software related. Some sort of incompatibility, somewhere. I'm not sure where else to look in terms of logs. Any suggestion at all, would be greatly appreciated.
Thank you for your time.