Toshiba laptop alternating blue and black screen

[Missislippy]

My Toshiba Satellite laptop (which is about 3 years old) has suddenly stopped working. When I switch it on, it powers up (fan running, all LEDs showing on the front), the screen goes a bluey-grey colour with a short white vertical line in the top left corner (like a cursor but vertical instead of horizontal), then it goes black, then it goes back to the blue-grey screen, then black again, continuously. I replaced the one 2GB RAM with two 4GB RAM last week in order to speed up W10. Would that have anything to do with it? I've tried removing power cable, removing the battery and holding down the power button but nothing happens.

 

[webworkings]

Try this...

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.