Solved! Laptop switches itself off after I turn it on, screen dead

[Ruger84]

When I try starting my laptop, Samsung NP350V5C Windows 10, the screen doesn't come alive and laptop powers itself off in a few seconds.
I've tried hard reset without the battery but makes no difference.
Any ideas what the problem is?

 

[hang-the-9]

Sounds like a bad motherboard. If you take out the RAM does it beep or give you flashing error codes? Try different RAM, see if it boots without the drive to the BIOS screen.

 

[Ruger84]

Sounds like a bad motherboard. If you take out the RAM does it beep or give you flashing error codes? Try different RAM, see if it boots without the drive to the BIOS screen.

I tried swapping out both RAMs with some old ones I have, didn't work.
I then tried swapping out the SSD for the original HDD, didn't work.

While I was at it I decided to keep striping it apart to clean any dust out of the fan. I noticed the CPU thermal past is crumbling.
Would this cause an issue on startup? Its 6 years old.

I was hoping it would not be a bad motherboard.