Two days ago, my iMac started behaving like crazy, with spinning wheels to death, hanging apps and file permission failures. So I ran Disk Utility which found and repaired a bunch of things, while "Repair Volume" recommended to backup all my stuff and reformat the drive. Done - nothing helped. This morning the drive was really stone-dead. So I decided to change the HD myself (following some HowTo's from the web). I bought a new WD 2TB HD and replaced the dead drive with this one. Now that I try to boot from my Snow Leopard Install DVD, it won't find the virgin drive or even start its Installation app, but simply jump to and fro reading some stuff, while the white screen shows a gray folder with a blinking question mark. Well, that's my story so far. Is the drive which I bought, too big for the iMac 7,1? What else could have caused this issue? Any help or comment is really appreciated.