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I recently added a second hard drive to my computer and I am using it do dual-boot Linux (Ubuntu 12.04) with Windows 7. Both hard drives are SATA. I am using the default grub bootloader on my second hard drive. The windows drive is unmodified. To get to grub, I changed the hard disk boot priority in my BIOS (P35-DS3L) to boot from the second drive.

The problem I'm having is that when I boot to Windows 7 (on sda) from grub (on sdb), Windows 7 will not go to sleep (from the start menu). The display shuts off momentarily as if its going to sleep, then comes back on and displays the switch-user screen. Powercfg -lastwake does not show anything.

I am sure that this is related to booting from grub on sdb because when I change the hard disk boot priority in the BIOS to boot from my (unmodified) Windows hard disk, the computer goes to sleep fine.

It occurred to me that installing grub on sda might solve the problem, but I'd rather not since I like to have my windows hard disk unmodified so that booting to it from the BIOS boots directly to windows.

A possible work around is to use the BIOS as a bootloader, by pressing F8 to select the boot device. Still, I'd like to know why the problem is happening in the first place.

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I have the same problem:… The sda does not make any difference, I have grub on that and win7 on sdb. Btw I think changing sata data slots would do the same in your system. It might be ubuntu related, I have 4 mints and 2 ubuntu on the first HDD. I'll install Fedora too, I am curious. – inf3rno Sep 16 at 4:29
I was never able to figure this out. These days I'm just using my BIOS to select the boot device. One HD boots windows. The other boots GRUB but then goes straight into Linux. – mkasberg Sep 16 at 22:20
I think we should send a bug report to GRUB developers, but I am not sure where to send that report. There are a lot of GRUB repos on github, and most of them have just a few stars. I am not sure which is the original. – inf3rno Sep 16 at 22:38
I wasn't able to report the bug here: I sent an email and attached my report, maybe they'll add it to the system. That's all I can do. (Lol I just checked, I wrote havannah instead of savannah to the email. :D ) – inf3rno Sep 28 at 20:53

1 Answer 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.

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I know that marking a partition as active works when you are dual-booting from a single hard drive, but it does not solve the problem for me when windows is on a separate hard drive. shutdown /s is a good suggestion that I have not tried, I'll have to see if that works. – mkasberg Nov 2 '12 at 20:36

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