g4

Hi everyone, I think I might need some suggestions here on a problem I'm having with my office laptop, a HP250 G4. A few days ago I started having this issue: when I press the power button, the CPU fan skyrockets to it's speed limit for about 60s without any display on the screen, then shutdown...

My LG G4 won't turn on and if it decides to do so it can't get past the start screen. I've tried taking out the battery and charging it overnight but that didn't work. Sometimes when I do plug it up I can get the battery percentage but then I goes to the start-up screen and can't get past it...