Samsung 15" Series 9 NP900X4C with Ivy Bridge CPU

Have you tried a battery reset?
This workaround at least helps on my linux driven 900X3E when ACPI functions are messed up.

 

Interesting idea - are there any risks associated with a CMOS reset? I have secure boot turned on. I am a little hesitant to do it without understanding...

 

It shouldn't be dangerous. The CMOS data are kept separately from UEFI. I tried a CMOS reset when a BIOS update appeared to brick my computer (I eventually figured out that the BIOS no longer supported 1.35V RAM).

John

 

I'm not sure if you got me right.
I was talking about a simple battery reset. While turned off hold the button in the pinhole on the bottom of the laptop for a while to disconnect the battery. You then have to use AC to be able to start the machine once again.

 

I would clarify that procedure:
1. Unplug the AC adaptor
2. Poke something firmly into the battery disconnect hole on the bottom (there should be a small click)
3. Try turning the computer on (it shouldn't start) but then hold down the power button for a minute.
4. Then plug the AC adaptor back in and press the power button ( the computer should start and the battery is automatically reconnected).

John

 

Haha... good on ya!

What's that good for?

For whatever reason my laptop doesn't turn on when the power button is pressed straight after a power down. However holding it will eventually turn it on.
Is that what you want to make sure is not happening?

 

Yeah ! It worked. After the battery reset, brightness, sleep on lid close, and airport mode all work again ! Thanks a lot. Makes sense in retrospect that ACPI parameters were wrongly updated at some stage (perhaps by 8.1).

As others have reported, after sleep requires power button to wake, but i can live with that.

thanks again oled and John!

 

The reason for holding down the power button is to drain any residual power. (But a minute is probably excessively generous).

My X4C starts with a quick poke of the power button. Yours sounds as if it has got another glitch. I've seen a few reports of similar problems. Have you played with the startup options hidden away on the Charms bar? Change PC Settings > General > Advanced Start-up.

Good news.

Thanks for the update.

John

 

Thanks for feedback!

That bug mostly gets triggered when supending to RAM (sleep mode). Good to know that bug doesn't only occur on linux.

Hope Samsung will fix this!

 

Maybe the power led just goes off before the system has completely shut down. If I wait 2 seconds a quick poke is enough to start again.
It doesn't really bother me though, I was just curious if that is what you were trying to work around.