I have an ASUS K55N which was new at Christmas (2012).
I had a weird thing happen the other day that I am trying to understand.
I disconnected the AC from the laptop and then attempted to do a normal Windows shutdown. (I am running Windows 8, 64 bit). Everything seemed normal except that the light on the power button wouldn't turn off, no matter how long I waited; even though I waited quite a lot longer than is normally necessary. Finally, because I was in a hurry, I just closed the laptop, put in its carry bag, and went home. Upon arriving home, I powered up the laptop and, instead of booting up, I found I had only the cursor, which moved when I gestured on the touchpad. I waited several minutes but it refused to boot up. I pressed the power button momentarily and that changed nothing.
I grabbed the manual and found a discussion of the various special features of the laptop, particularly the Power4 Gear Hybrid application. It occurred to me that the laptop might be asleep and that Power4 Gear Hybrid might have been responsible. I hit Fn-Spacebar to bring up the Power4 Gear Hybrid application so that I could bring it out of sleep mode but nothing happened when I did that.
Finally, after trying a bunch of other things that didn't work, I just held the power button down for several seconds until the power light went out. This time, I got a Windows logo and thought I was back in business. But I wasn't quite there yet. A test of my memory commenced which ran for a rather long time - around 40 minutes - but it revealed no problems with my memory. After that, I was able to reboot back into Windows normally.
I'd like to find out a few things.
1, Why wouldn't the laptop shutdown properly while running on battery power? Is there some special technique I need to use when shutting down while on battery power?
2. When I looked at Power4 Gear Hybrid after my successful reboot, I found that it was set to go to sleep in many different situations. I'm fine with that but I'm not clear how to wake it up when it is asleep. What is the proper technique?
3. Why did that lengthy memory test run? I'm not sure if that was triggered by the hardware detecting a particular problem or if I inadvertently did a key combination that initiated it. I had tried a lot of things, including all the Fn key combinations to try to wake up the laptop before holding the Power button down. Maybe one of those combinations got remembered at bootup and told the computer to check its memory? I really just want to avoid initiating a memory test unintentionally.
Sorry for the long post but I wanted you to understand what I'd done.