As the title says, as soon as I start up my 2006 model 24" iMac.. OS X crashes and I don't know why heh. I'm running Tiger also. The crash happens after I select OS X from the Bootcamp screen. (I have Bootcamp from the Beta still) It gets to the little gray Apple symbol, loads a little and then just crashes. I suspect it has something to do with when I updated my 7600 GTs graphics drivers in Windows as Windows continues to not work also on boot up. You may say it's a broken mobo or displaced RAM but it isn't. When I uninstalled the the graphics cards drivers in Windows I was able to boot fine into it. The nVidia Forceware drivers were the cause, they said they were bug free ha.. if you check the nVidia forums you'll see a lot of people have this problem with Windows. But back on topic, I've tried reinstalling OS X by trying to boot to the disc when holding down C.. it crashes. Holding down shift.. it crashes. If anyone knows how I can fix this problem, please tell heh.