Inspiron 6000- Screen goes black or white suddenly

I'll be using my laptop and all of a sudden it goes black.  None of the keys respond and I have to turn it off.  It happened once when I was watching something and the screen went black but I could still hear the show.  It has been happening more frequently and recently it turns completely white instead of black, but it's the same problem.  Please someone help.  I went to the support site and it says to download the most recent video driver which I already have.