Hi, I have a iMAC G5, Intel Dualcore running Tiger OS. Recently I have been unable to get it to start. I get the welcome chimes, goes into a gray screen with a folder with a question mark blinking. It does not go beyond that. I've tried to run the start up disks that came with the desktop, but my HD doesn't appear on the screen, nothing does. I've tried PRam, disconnecting the power cord, the accessories and nothing works. It has worked a few times after I turned it off for awhile, but then the same problem come back. Lately it has not allowed me to start up at all. It's as if the HD isn't there. I don't hear any odd noises. Any suggestions on what it may be and how to remedy this? Many thanks before hand.