If it's only the display that doesn't work, which from your previous post it sounds like it is, and external monitors don't work either then it's probably the graphics processor, and not the display itself, which makes it worse, because the display is relatively easy to replace.
Getting a refund is your best shot.
Just to double check, the computer is booting fine? You could maybe find a video of someone powering it on (the same model or similar), observe how it should behave and compare it to what's happening with your computer. If you notice something odd you may find that the problem is somewhere else.
Either way I'd try to get a replacement or the money back.