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Now, my Windows 7 system will only turn the screen black and then is immediately woken up after I hit the sleep button, through either start menu or the keyboard, and the same issue exists with hibernate.

The recent changes I made are hard to remember, but:

  • I did install OSX on my machine, prior to which I reset the BIOS, and also changed the sata mode to AHCI (I tried putting it back to IDE with no luck)
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I found that it's AHCI was the key for me as far as Windows 7 sleeping, and I too had OS X installed on a second HD. When I temporarily took OS X off and set the bios back to IDE, I could put Win 7 to sleep. However, Win 7 does go to sleep on it's own via power settings in AHCI.

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If you have reset the BIOS you should configure it again, it's possible that the sleep support is disabled.

Have you installed all the drivers after your reinstall? Be sure to have the chipset drivers.

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I have already reconfigured the BIOS, and there was no need to reinstall drivers as I am using the exact same install of Windows 7, which is why it is strange - I didn't reinstall/change anything in Win7 and yet it won't sleep. – user46073 Aug 13 '10 at 6:34

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