My laptop's currently having a problem where it's turning on normally but the screen stays black. Now, I want to project my laptop to an external display (and preferably, if possible, to another laptop) to see if it's a display/screen issue or if it's a GPU issue. The challenge here is the the screen is black, so I don't really know how I would be able to verify that it's projecting. I don't know if I worded this well, but I think my point got across.
To another laptop wouldn't work. You would need to try it on an external monitor.
Turn the laptop off (not sleep or hibernate but off).
Connect an external monitor to the laptop.
Turn on the external monitor.
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.
You may also want to try hitting CTRL + SHIFT + WIN + B to try and reset your graphics driver as another possible fix.