Can't be the aquaero because without power it won't do anything
I had the same problem and the reason for that strange behavior was an update task that was allowed to wake the PC even in standby.
Go to the control panel, administrative tools, event viewer, windows logs and finally system. Click the column source to sort it alphabetically. Search for power troubleshooter and a date and time where your system started without doing anything. In the window below you can see what has caused the start of the system. I'm pretty sure you will have a similar problem there.