Laptop screen black and fan om max

[karlsimon0502]

When I press power on my laptop it won't start up. After the button is pressed, the power, Wi-Fi and the mute button lights up. After a few seconds the caps lock and the scroll button starts to blink three times then goes black, this repeats like 7 times and after that the fan goes on to max speed and the screen is still black.
Help!
The laptop is a hp proobok 430 g2

 

[webworkings]

So it is powering on then, but no display and fan running to fast. First try this and see if you can actually see what is on the screen, to determine if there is any error message, etc...

1. Turn the laptop off (not sleep or hibernate but off).
2. Connect an external monitor to the laptop.
3. Turn on the external monitor.
4. Turn on the laptop.

NOTE: You may have to press an "external monitor" button. Could be the f4 button or a button with two monitors on it, for the external monitor to work.

If you can see fine on the external monitor, then your attached display, or the ribbon cable that connects it, are your problem.

If you can't see on the external monitor at all, or the problem occurs on the external monitor as well, then it is probably the graphics card/GPU that is the problem, which may require the motherboard be replaced.