Hi I was using my powerbook normally, and it suddenly crashed. I tried restarting it, but it refused to start up. It gets to the apple logo with the spinning circle beneath it, and just stays there. Starting in safe mode resulted in the exact same thing. When trying to boot from the install cd to check the disk and repair permissions, the apple logo simply moved half an inch to the right and it crashed again. If I use the option key to select the cd before startup, I get the apple, then a "no entry" sign, a circle with a diagonal line through it. Any help is appreciated.