Hello!
I had a terrible time trying to get my ASUS K52 laptop to sleep and hibernate (win 7 home premium). I scoured the net looking at all kinds of things like using the commands:
powercfg -a
powercfg -devicequery wake_armed
sfc -scannow
I tried to boot into safe mode and never did figure out how to actually do that. And so on and so on...
I was really motivated because if I was running on battery, it would just completely drain the battery and crash hard.
The display would dim and turn off as expected but it would never sleep and certainly would not hibernate.
I finally figured out one problem was that my wife was logged in on my laptop. I did not think that would be a problem. Sometimes she uses my computer when I am away and then do a "Switch user" but NOT a logout.
Apparently, this will stop your laptop from sleeping. Once I logged her out, then it I could sleep at the expected time. But it still would not hibernate or turn off hard disk. So I went through all the advanced settings, yet again, in my power config window, everything made sense and I followed all the recommendations for the various settings I saw online. Finally just pressed "restore defaults" and Whaddya know?! Hibernate worked at the expected time. I used the "Balanced" power plan.
Now, FINALLY, my laptop works as expected and I really like the "Sleep" mode and it goes to hibernate overnight to save even more power. Life is GOOD!
Hope that helps anyone struggling with this stuff.
I don't why it was so flaky before. It seemed like I had a virus that was monkeying with my power settings but it's been working perfectly for over a two weeks now so I think it's licked.