I have had my iMac for about 2.5 years. I am currently running Snow Leopard. When I go to use it, I can only use it for about 10 minutes or so until the screen freezes up, and small, light blue "dots" appear all over the display. If I turn it off and then turn it back on again, this screen appears (see attachments). If I wait around two minutes instead of turning it off again, the dreaded gray kernel panic message appears. It should be noted that none of these problems occur when I start the Mac in Safe Mode. I originally though it was an overheating issue, but I tried it a couple times today, and the Mac doesn't seem warm at all. Does anyone have any ideas of what could be going on? Thanks.