Black Screem I-mac G4


I bought a MAC G4 and it seems to have problems with the Panther OS X and the sleeping mode. It's the second time that the screem becomes completely black, it doesn't matter if I force quit and try again and I can even hear that the computer is working fine. I tryed to start from the CD, but it also didn't work. I've heard about the sleeping problem that even if there is a OS upgrade, it'll still have the problem (or a different one). Could you please advice me of the best thing to do?
What version of Panther do you have?

Go to your Apple menu, and choose about this Mac. You should see a 10.3.X number.