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Until recently, I experience something rather annoying (and troublesome) with my laptop. It spontaneously shuts down itself without any warning, it restarts. No blue screen, no hanging program, just everything is going on smoothly and the computer shuts down similar to a desktop facing power fails, without UPS.

Here's my laptop's conditions and my guess:

  • It's rather new (model Asus K53SV, I bought it this time last year). Running core i5 2430M, 8GB RAM; OS Win 7 Ultimate 64 bit, SP1.
  • The shutting down occurs randomly, not too frequently (may be once a week, maybe 3 consecutive days, once a day, may be 2 days OK than happen the next day,...) but recently it happened more often.
  • I always use my laptop with the battery installed, and one AC line. The battery will be charged fully to 100%, then the computer states that it's running on AC line. After a few days, when the battery level drops below 95%, the charging will begin again until 100%.
  • The shutting down occurs even when th battery is fully charge, and the laptop is on AC line.
  • No problem with Windows after the event, I start in safe mode, then restart again to make sure everything is OK. In the Event Log of windows 7, it store faults related to "Kernel Power Failure" or something
  • I use the laptop on battery once or twice a month, making the battery drain to below 10%, then charge it to 100%.
  • Please don't tell me that this is the overheating problem. It's winter in here. The ambient temperature is about 17 oC, and the Aida64 report CPU & GPU temp of 46 oC, fan speed 100RPM. When I stress the CPU to test, the fan speed adapts quickly, it can reach 3800-4300 RPM, and the CPU temp never gets higher than 70 oC.

So here's the question: What unit/chips control the current between the adapter output, the battery and the mainboard? Is it the role of the chip inside the battery? Can a faulty battery the cause of the problem, e.g "the 'digital' switch back and forth" to control the current got problem?

  • For now I uninstalled the battery, running on adapter only. However, due to the randomness of the shutting down, I need to check on this condition at least 4 or 5 days to narrow down the possible cause. Just don't want to make my laptop running on AC line only in such a long period, because I don't have UPS.

Any experience or explanation would be appreciated. Thanks.

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Although you have given us a lot of information, there are some key things you've left out. Have you run any hardware (Asus) or Windows 7 diagnostics (Control Panel\System and Security\Find and Fix Problems)? Does the problem occur when using only battery power? Does it occur only AC power with the battery removed? Have you checked for BIOS and/or firmware updates from Asus? – CharlieRB Feb 1 '13 at 12:58
Thanks for your suggestions. I haven't tried Windows 7 diagnostics. Will give you answer after I run it. - Up until now, the problem seems to happen when both battery and AC power are on. I'm on the 2nd day of trying adapter only, with battery removed. Nothing bad so far. After this test, I'll test with battery only. Actually the battery can last for more than 3 hours. – Jim Raynor Feb 1 '13 at 15:31
I had this happen with my Sony Vaio when it was fairly new -- the unit would click and shut down hard. After mucking about I discovered that the unit would run just fine if NOT plugged in to the AC, and eventually I determined that the battery was being overcharged (or at least the unit thought so). Running the unit a couple of hours on battery temporarily fixed it, and using the Sony-specific "battery saver" feature to not charge over 85% permanently fixed it. The charger circuitry can get confused, especially on a new unit that's used mostly plugged in. – Daniel R Hicks Jun 22 '15 at 11:38

Your computer's internal power supply might have a problem, based on the scenario you just described. A common fix that I use with clients who ask me, and whenever I am having issues, is to unplug the battery and the power cord, and press and hold the power button for 60 seconds to eliminate all charge built up in the computer. Then, plug in the power cord but NOT the battery. Turn on and off the computer (properly) and then replace the battery and charge it up. If this doesn't help, you might have a defective battery. However, in normal circumstances, you should be able to remove the battery/charger as long as one or the other is present (a computer only needs one power source, two is helpful in case one fails.) If both are present and the computer fails, this might signify internal power problems.

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I think your laptop battery is not storing charge any more and behave like a short to your laptop power supply circuit. I have these happened with 3 different laptops - two Dell and my daughter's Acer.

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