Happy new year, guys! I'm opening a new topic 'cause I couldn't find answers for my questions after 3 days of googleing around. Long story short: I was browsing with Chrome, couple of tabs opened, the mail app, skype, finder and a couple of more "inoffensive" apps opened, I can't remember exactly, and suddenly my iMac rebooted. At least tried to. Since, I couldn't start it. Sometimes I got stuck at a black screen, sometimes at a white one, and sometimes it starts and shows the apple logo and the loading circle than back to the white screen, and sometimes the chime is looping. I managed once to boot into Disk Utility with command +R and start the disk repair, but it restarted.Same thing happened when I gave the fsck command in single user mode. I noticed that it reboots when its loading something related to Parallels, but not sure that's the problem. Then I tried everything: -verbose: no success: restarting. -boot from disk: restarting -netboot: restarting. -command+R: restarting -single user mode: restarting after a couple of minutes of inactivity. -can't boot to Disk Warrior. -safe boot: nothing -Apple Hardware Test not working -SMC & nvram Reset: several times, nothing changed. -changed memory modules to the original ones at 2GB My mac: osX Mountain Lion 10.8 Model Number: MB398 Machine Model: iMac8,1 CPU speed: 3.06GHz 24 inch Any help will be truly appreciated. Thank you.