Acer Aspire F5-572G-563Q won't turn on

Pompan

About three months ago, my Acer laptop died without any explanation in the blink of an eye while I were using it. It went black and refused to reboot. 
Since then I haven't managed to reboot it.

Pressing the power button makes a blue LED flash once at the bottom left of the computer and a clicking noise is made. Holding down the power button loops this process in ~2 second intervals.
From what I've already read it seems to be a problem with the motherboard.

Here's what I've tried so far:

-Remove the battery, plug in AC.
-Remove both battery and AC, hold down the power button for 60 seconds and wait 20 minutes. Plug in AC. (This is the only option, while both battery and AC is out, that a clicking noise and blue light won't flash). 
-Same as directly above but repeating the push down power button for 60 seconds process 2-3 times before waiting 20 minutes. (I've also tried leaving it overnight before AC is plugged in).
-Remove RAM-card (while power is out) overnight before replacing.
-Remove CMOS-battery (same time and duration as RAM-removal before replacing).
-Connect laptop to external monitor. I've done this to another laptop USB-USB for the heck of it but nothing happened. 
I connected it to an external monitor by D-SUB cable. I can't remember what the external (working) screen said but something about nothing being detected.
-I've removed the hard drive - which works. I plugged in the hard drive into another PC and it worked properly.

I have never spilled any liquids on the laptop it has never been dropped or been abused.

If I connect the laptop to a power outlet, that I know is working, an orange LED with turn on, and stay turned on, right next to the blue LED. If I then press the power button the blue LED turns on, then both lights turn off. A second later the orange light turns on again just as before.

Any suggestions for further tests or something?

Thanks in advance.

Rudy21

@Pompan

Looks like you have already tried almost all possible ways to power on the unit. For me it looks like an issue with Motherboard. if you think you have warranty then i would recommend you to contact acer support.

Pompan

Rudy21 said:

@Pompan

Looks like you have already tried almost all possible ways to power on the unit. For me it looks like an issue with Motherboard. if you think you have warranty then i would recommend you to contact acer support.

Sadly, the laptop is about 3.5 years old, so I do not have a warranty that I know of.
Is there a way to check if the motherboard is dead or not?