PC not booting - Can't acces BIOS

Hi,

This is the first time I post here and one of the first time I post on a forum asking for help. Usually i find answers looking for help but this time i have a big issue and I need help. I hope any of you guys will be able to save me.

Here's the story : A friend of mine asked me to fix his Acer Aspire S7-391. He couldn't boot on W8 due to an 0xc0000001 error.
Before doing anything to his computer I tried to boot on different liveUSBs of linux distros so I could copy some stuff from his hard drive to my external one. I couldn't boot on any of them.

I went to the bios and tried to disable secure boot thinking it was the problem and i couldn't disable it.
Even though i couldn't backup any file I decided to repair the windows issue. I made two USBbootable copy of windows8 : one with Rufus, one with the windows tool. I still couldn't boot on any one of them.

So, this is where i failed hard, I went to the BIOS and changed from UEFI boot to Legacy mode.

Now the computer won't even start, the led lights on for 1sec and goes off. I can't access to anything. Is there any solution ????

Thank you for reading me.

Sounds like a RMA to me, if you can't even get to the BIOS again it sounds like it bricked. You could look on the Acer support forum there may be a last resort way of installing a good BIOS file.

Is this PC a desktop, with a removable CMOS battery, or a laptop, with a hidden CMOS battery?

If a desktop (you never did say) unplug the PC and then remove the CMOS battery for at least 30 miniutes.
If you can, check the voltage on that battery..... it must be at least 3.0vdc or it should be replaced.
Batteries with voltages under 3.0 vdc, can cause the PC to do weird things.

Then finally, put the battery (or a new one) back in, restore the line power and again try to boot up the PC.
If this master reset to the bios worked, you will have to restore the time and data and boot order.

I've used this technique many times to restore a PC that would appear to be DEAD.

Good Luck,
TechnoMage

And if you notice the motherboard in the computer or on the back of the computer has a light showing after you unplug the power cord, press the On|Off switch or wait about 30 seconds for the light to go out meaning any residual power will have drained off. A feature of modern ATX motherboards is that there is power to them all the time they are plugged in and the On|Off switch only wakes the motherboard up to get things started. Not draining the power can cause problem when working on the board or any add-ins. The older AT boards were different, had the On|Off switch connected directly to the power supply.

First thank you for your answers.

It's a laptop, more than a netbook its an ultrabook. I don't even have access to the battery without opening the main case with a torx screwdriver.

Changing/Reseting the CMOS battery of the motherboard doesn't seem to be an option for now.

I didn't really understand how the feature of the ATX motherboards can help me but i already tried to unplug the power supply, tried to shut down the laptop, tried to wait (more than 30 sec ).

It keeps on rebooting : for 1s(led on, screen back-light on) and then off for like 3-4sec. I can't Fx, Esc or anything to get to the bios or to anything.

If i was on my laptop the first thing I'd do would be to remove all electricity from it and try to plug it again. But I don't have access to the battery...

To me it looks like its either RMA like Clintlgm said or I open the laptop.

Actually I had access to the battery. Well kinda. There's an opening like the ones on pocket calculators to disconnect the battery. I tried it a few times, even a 30+ sec one.

Things are still the same. No logo. No text. Nothing. Just a screen backlight.

Anyone got a brilliant idea ?

trying removing the HDD / SDD and see if you can get into Firmware Settings

If possible an external monitor ?

Unplug the power pack, remove the battery, press and hold down the power button for 10 seconds or so. Plug the power pack back in, battery too if you want, and have another go at getting into the BIOS..