Hello guys, I've been running my imac for about 3 years and have never had a problem until last week. It randomly crashed (screen darkened and told me i had to reboot in a couple different languages) so i rebooted and then it ran ok for another few days. Yesterday it crashed again and when i rebooted it crashed before getting past the gray screen with the spinning wheel. To troubleshoot i followed all the things on the post i saw here: http://guides.macrumors.com/Mac_doesn't_boot but nothing is working. I am able to run the hardware test successfully and no problems were found. next i tried to get it to boot from the original install disk that came with the computer to run the disk utility but i was unable to get that to run (it crashes at the gray screen). Then i tried to boot in safe mode which again crashes at gray screen (when holding shift on boot, it take considerable more time on the gray screen before crashing). I'm starting to get pretty frustrated. I've never really troubleshot problems on a mac because it's been working so well i've never had any real issues with it. I'm not sure if this is an advantage or not, but i have all my important info stored on an external hard drive so i am definitely not against wiping the drive and starting fresh but i'm not even sure how to do that lol. What do you guys think? Any info or suggestions are greatly appreciated.