Laptops :: IBook G4 Display Goes Dark

I have an iBook (OSX 10.3.9)that's been great for the last couple of years. However the last week or so the screen goes dark for no apparent reason. You can still see through enough to fiddle around and hit shut down...and after it shuts down, and I restart it...it seems normal...that is until the next time. It's happened about 4 times in the last three days. A couple of times on battery and once plugged in I think. It's like it goes to sleep but you can't hit the space bar to wake up. Also seems like maybe an energy saving deal gone awry.

Now for info that may be pertinent: I dropped this laptop(in it's case) about a year ago. Holy crap..all docs would only read in magenta. No black no color only magenta and a "photograph negative" looking image for background or any graphic. I was sure it was dead duck and fried but kept trying it periodically. After about a month, after giving up...I turned it on and it was fine...as if nothing was wrong. Weirdest deal. It's been fine ever since.

I thought perhaps I was too lucky...and assume this may be a result of that fall.