I have a 1ghz 15" TiBook. Just a couple days ago, I successfully (?) replaced my old dead combo drive with a new 8x superdrive. Upon initial restart, the drive worked, my computer started right up as well. I was happy. I was running it with the battery out, so I shut it down, put the battery back in, started up, then it loaded the desktop but hung just before it loaded the Airport icon on my menubar. Spinning beachball. So I force quit, then tried to restart, and I got absolutely nothing, no chime, and just a dark screen. Sometimes when I try to start it I can see the display flash but nothing further. I can hear the superdrive spin on startup but get nothing else. I put the old drive back in, and still no response. I tried to reset the PRAM; found the reset button under the keyboard and tried that, still nothing. Is it the logic board then? Ugh.