HP Probook suddenly not booting up/weird sound

[AzeofSpadez]

Hello everyone!

I got to take over a HP Probook 4710S after helping someone with some "technical issues" since he was buying a new anyway.
I used it a few hours for some days installing different Linux-distros, Windows 10 and whatnot just to see it's performance.

What I noticed was both that the CPU heated up pretty darn good when under stress (Up to 95C) and that there was something really wrong with the battery since it only made it like 10 minutes before it died with an error message upon startup saying that the battery needs replacing.

And then one day all of a sudden it wouldn't turn on properly.
I used it the night before and it was working great and turned of the way it should but it just wouldn't start up and it's been the same ever since.
I really don't understand what has died because with or without the battery it should boot up into BIOS and give me a monitor signal, same goes if the internal battery on the motherboard has died as far as I know.

I'm not intimidated to open it up at all since I'm a "tech" but the problem is really that I don't understand what has been damaged.
Is something on the motherboard dead?

Here's a video of how it looks when I boot it up: https://www.youtube.com/watch?v=0RPqOOv7DGs
Does anyone have a clue of what's wrong here?

[OhpUldum]

Try removing the battery, unplugging power cable, hold down power button 30 seconds. Keep battery removed, plug in power cable, and power it on.

In regards to high CPU temperatures, if you want look at cleaning out all the fans, and applying new thermal paste to the CPU.

[AzeofSpadez]

Try removing the battery, unplugging power cable, hold down power button 30 seconds. Keep battery removed, plug in power cable, and power it on.

In regards to high CPU temperatures, if you want look at cleaning out all the fans, and applying new thermal paste to the CPU.

Unfortunately that didn't work.
Yeah I know that's a good idea to do but with the computer acting bricked like this I'm thinking about whether or not is is even worth my time because it seems broken in some way or another and I wondered if maybe anyone have a nidea of what's broken or what is wrong?

Becuase if the motherboard is toast or something like that well then I'll just salvage the HDD/RAM and throw it away.

[OhpUldum]

Yeah based on the video it looks like a power issue which is why I started basic with the unplug, etc. Could easily be a toasted capacitor on the motherboard.