[SOLVED] Laptop Asus N56VB with trouble powering on until POST

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brunoais

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Aug 27, 2013
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My laptop, an Asus N56VB, has been having some trouble executing the POST and I've been unable to diagnose it right.

I power it on and it turns off. Then it powers on again and executes POST correctly.

If I remove the AC power and try to power it on with the battery, it won't power on again until I do a CMOS reset (when I press the power button with the AC cable off and no battery). In other words, it's impossible to power on using only the battery.
The battery is working fine, it is capable of powering the PC. It lasted in today's test for 1h17 minutes to reach from 100% to 5% while playing Bioshock Infinite windowed (with some programs in the background). So the battery is good.

Here's a video of it failing and executing the POST until the phase it asks for the HDD password:
Faulty laptop - YouTube
The beeping sound comes from an external HDD that beeps when its power is cut off or when it doesn't have enough power. I'm not breaking it, don't worry.

I also tested this without an HDD password and the problem persisted.
If I suspend, it loses the suspension state when I try to power it back on because it powers off before rebooting.
Hibernation works as expected without any surprises. Both when I execute the OS shutdown and when I execute the Hibernation command.
The CMOS battery is at around 70% capacity.

I miss the BIOS beeps...

What can I do to diagnose this? What can I do to fix this?
 
Re: Laptop with trouble powering on until POST

It is a very strange problem. When did it start? Did it ever work correctly? What change happened just before you first noticed the problem?
The CMOS battery is at around 70% capacity.
Click to expand...
How did you determine that? I would still replace the CMOS battery (if you can get to it okay - not always easy in notebooks).

One thing that comes to mind is your hard drive. It takes a LOT more power to "start" a motor spinning and get it up to speed, than it does to keep a motor spinning at speed. That could indicate a motor problem, or your battery, while indicating a full charge, is not really putting out the necessary voltage. Is that the original battery. How old is this battery?

I don't believe interrupting the boot process before it has a chance to complete is helpful either.
 
Re: Laptop with trouble powering on until POST

This started at around 4 months ago but it didn't fail to start using only the battery until last week.
I installed windows 10.

I used a voltmeter and a simple circuit specially made to close the electrical circuit in a battery and get the amount of energy left through a test. I had done that test at the end of November. It gave a result of 70-72% after applying the math based on the maximum expected voltage, the voltage measured when energy was only passing in the multimeter and when there was a closed circuit additionally to the multimeter.
The CMOS battery can, at least, hold the clock just find on a night without power and with the battery removed (I tried it last night). So I guess the test was, at least, potentially credible...

The HDD motor can stop and start just fine when I'm using the PC. The OS stops it when it is not in use when it is on battery mode and it restarts just fine without any noticeable delays compared to when I use AC power. This is the original battery. I don't know how old it actually is as I can't find its manufacturing date but I know it was bought almost 4 years ago.
The HDD starts spinning just fine when I try booting using the battery.
When I'm on battery mode, I can simultaneously start 3 portable HDD with no problem both when the OS is running and when I'm in a BIOS screen.

According the the machine's spec, the logo screen only appears after POST is complete and it stays with that image doing nothing just waiting for a timer to end and then move on to the next thing.

If you notice, for some reason, after trying to boot using the battery, I can't get it to boot (even with AC) unless I reset the electrical system by removing both the battery and AC power and pressing the power button. That's also weird to me...
I've had been having laptops that last about 5 years before I change to a different one and the only thing that has been noticeable to change over time in all of those is the battery which would have diminishing power, except on one PC that fried the battery on a power surge near its EOL.
So I don't really get what I did wrong with this PC.
 
Re: Laptop with trouble powering on until POST

Well, you've clearly done some extensive digging into this. Not sure what else I can suggest to try. The CMOS battery keeping the RTC (real-time clock) ticking is a good sign the CMOS battery is still good. But the RTC is a separate tiny chip that takes very little power to keep going. Since they are only a couple bucks, little is wasted if not the problem.

You said,
This started at around 4 months ago but it didn't fail to start using only the battery until last week.
I installed windows 10.
Click to expand...
What does that mean? You installed W10 4 months ago and the problem started? Or you installed W10 last week and the problem got much worse?

It would be nice if you had a second battery to see what happens. Are you able to calibrate the battery? Generally this requires you run the notebook on battery until the notebook automatically shutsdown. Then you charge it up again. This may have to be done a couple times.
 
Re: Laptop with trouble powering on until POST

I think it is also quite normal that the CMOS battery is at a very high power because the PC is always with the battery placed in.

Digerati said:
When did it start?
Click to expand...
This started at around 4 months ago but it didn't fail to start using only the battery until last week.
Digerati said:
Did it ever work correctly?
Click to expand...
It worked correctly for some years.
Digerati said:
What change happened just before you first noticed the problem?
Click to expand...
I installed windows 10. I installed it 4 months ago.

Going back to windows 7 didn't fix it and reinstalling windows 10 also didn't fix it. I do believe it is a coincidence, though. They act on largely different places. I don't think windows ever does anything to the BIOS. At least, that's what the technical manuals and all other stuff I could find says.

I really forgot about battery calibration! It's been quite a while since I had done it (~9 months?)... I'll do it right now. I'll play a game, I should be able to empty it twice in 8 hours. Thanks.
Oh! I'll report back after I'm done with the calibration.
 
Re: Laptop with trouble powering on until POST

You didn't clarify anything. You are connecting a problem that started 4 months ago (powers on then immediately powers off) to a problem that started last week (won't start with battery only)when there is no evidence the two problems are related.

Let's hope the batt calibration helps.
 
Re: Laptop with trouble powering on until POST

Hum... Sorry I'm misunderstanding the questions... I'll try thinking differently.

The ON/OFF/ON problem started 8 months ago (sorry, I thought it was 4).
The battery problem started 2 weeks ago.
I relate the battery problem is due to something that happens during POST.
I have no idea if both are related but I thought it would be useful to show the other issue as they can be related.
The PC was working perfectly fine until the ON/OFF/ON issue (8 months go) without any noticeable issues.
The change that had happened was that I had installed windows 10 (8 months go) and all the requirements for it to work including drivers.


The ON then OFF issue and later a ON has a different thread. It's been a while but I was able to find it:
https://www.sysnative.com/forums/wi...t-shutdown-not-working-well-since-update.html
Also, sorry for my time mistake, it is not 4 months, it is now 8 months.
I let that thread die by mistake because I had forgotten about it and sounds like I missed the e-mail about his response...

It was hard to find the time to do the 2nd discharge right but it is done now. The calibration is now complete.
My PC still won't start with the battery for some reason.
I'll try again and differently tomorrow morning.

Does this help?
 
Re: Laptop with trouble powering on until POST

Does this help?
Click to expand...
Yes, thank you. But I have to say more confusion is added with your inclusion of the link to your other thread as you noted there (in April) that you upgraded to W10 4 months earlier.

Since I am not good with time either, we need to clarify. Did it ever work correctly with Windows 10?

I am at a loss for suggestions, but to try a different battery. But that would be an expensive investment with no clear indication it would fix your problem.

I note that OldGrayGary is pretty sharp in these areas so I am closing your other threads and will see if we can get his attention and focus here.
 
Re: Laptop with trouble powering on until POST

I already hadn't answered OldGrayGary because I was working on what he had said but meanwhile I had forgotten the thread existed.
I'm still exploring how other boot options can help me here I just don't have much free time for this, unfortunately.
 
Re: Laptop with trouble powering on until POST

OK, I found the issue.
After it failed for good to restart, I diagnosed the problem and sent the PC to a repair shop.
As I had diagnosed, it was the BIOS EEPROM which had corrupted data.
After they reprogrammed the EEPROM with the chip desoldered, in a chip programmer, it became working as expected and all the problems above didn't come back.
It's been almost a week now.
 
Re: Laptop with trouble powering on until POST

Wow! Not many repair shops have that capability, or know-how these days (except, maybe, warranty repair shops). I hope the cost of the repair (for labor) was not more than a replacement motherboard.

Anyway, I am glad it seems to be sorted out and thanks for posting your followup.
 
Re: Laptop with trouble powering on until POST

The cost was at about half the price of the motherboard and they also cleaned the whole inside of the PC and reapplied the heating paste on the CPU and GPU.
 
Re: Laptop with trouble powering on until POST

As long as you are happy with the results, that's good enough for me.
 

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