I'm trying to reinstall a fresh copy of OSX Leopard on my computer. After clicking restart from the CD installer the computer reboots and then I get a dark grey screen saying Please hold down the power and restart the computer. No matter what I do the same thing keeps popping up. I have't added any memory or changed any hardware. I ran techtool deluxe and everything looked fine. I've also zapped the pram. Any suggestions???? Thanks!