start up question mark
Why does the mac flash a question mark periodically
iMac, Mac OS X (10.5.8)
Welcome to Apple Support Communities
Your Mac can't find any bootable disk.
1. Insert the Mac OS X DVD and press C key while your computer is starting.
2. Go to Utilities > Disk Utility, select Macintosh HD in the sidebar and repair the disk.
If it doesn't help, the hard disk is broken. Take the Mac to an Apple Store