Something I noticed today, seems to happen mostly after waking from sleep, the Aqua computer service will be stopped.
Windows has many sleep / power off modes. Which mode are you using?
Well that's a good question. Even though Hibernation is supposed to be turned off, the other day I could not wake the pc from sleep and got a message that seemed to indicate the computer had entered hibernation.
So I disabled hibernation from the command line and I will see how it goes. Otherwise sleep is enabled in Windows 7 power options.
In the BIOS ErP is disabled, and C6/C7 is Enabled to attain the low power idle on my Gigabyte Z87 board.