Screen has green pixels instead of black

My laptop has green pixels where black pixels should be, so in other words when the Windows XP splash screen comes up during bootup the screen is completely green except for the logo of course. Every “true black” pixel is green colored and the problem is there when Windows is running too. I can see they are not dead pixels because all the pixels do it when a black pixel should be there. I had a friend who is a Toshiba certified technician take a look at it and he said it looks like coffee was spilled on it but the LCD is fine so it seems to be something with the onboard video. I am great with making and repairing desktops, but not laptops, though I could if I needed to. Can anyone suggest anything besides getting a new laptop or a new motherboard. The MB sounds better than a whole new laptop.
One other thing I should add is that when I bought it on eBay it was sold because of the little green pixels but it was reported as showing up here and there, when I actually received the laptop the problem was completely gone. Then I sent it to UPS because i filed a claim since they damaged the power supply and also the CD-ROM and when they shipped it back the green pixels then showed up and much worse. Nothing helps, twisting the LCD , banging it a bit, nothing at all helps it. So its weird because after I bought it from eBay UPS delivered it and the so-called problem was non-existant, then I sent it back to UPS, then they shipped it back and the problem was there. Can anyone help please??

There is no simple solution for this problem.  If the coffee went down to the motherboard, I think you’ll have to replace it.
By the way, what if you start the laptop with an external monitor? Do get the same bad video on the external screen (indicates a problem with onboard video) or the external screen works fine? If the external monitor displays normal video, may by you just have a bad video cable and there is nothing wrong with the motherboard? Test the external video before you make any conclusions.