Last Sunday my computer screen, that I output from my laptop, went jet black. When I touched the laptop, it was extremely hot.
When I turned the screen this was what I saw: http://i58.tinypic.com/sbihoz.jpg From this point, trying the graphics card will cause a blue screen and a continual reboot.
I tinkered around and was able to disable the video card but now this is how it looks, after I reinstalled Windows: http://i62.tinypic.com/1zxvdhs.jpg Once I get it to this point, the laptop is fully functional. I've outputted the to a monitor and get the same look.
You could try updating the driver. I presume this has been happening over several days/weeks?
It could be overheating if the fan vent at the side is full of dust, with laptop turned off, use a vac to suck it out (never blow it in) you might need a cotton bud/small paint brush to disturb the fluff.
Another thing you could try: power down switch all off, take out battery and power cord and then hold in the on/off button for about 30 secs to remove residual static and empty volatile memory. Then put it all back together and boot up.