Windows won't sleep after booting from grub
Solution 1:
I'm seeing a similar problem with Windows 8 and Ubuntu 12.04, but both OSes are installed onto the same HDD in different partitions.
If the Windows partition is active, shutdown works as expected.
If I make the Ubuntu partition active, and boot Windows 8 via grub, I can't shutdown (the screen turns black, and the HDD LED flickers for a bit, but the WiFi LED remains lit. If I touch a key or the trackpad, the screen wakes up, and I'm back into the Windows lock screen.
Interestingly, using the Windows "shutdown /s" command works, even when booting via grub.