I am the owner of a new 20" 2.4 Ghz aluminum iMac, which I purchased the first week they came out (2nd week of August). I have had no problems with the machine since I got it, until today. I have an extra 1 GB of RAM from OWC installed, but have had no troubles w/ the RAM since I installed it in August. This is my first Mac, so I am not familiar with the range of standard troubleshooting strategies, other than what I'm reading in the Everything Mac book today and in the MacRumors Guides. This morning, I woke my iMac up from sleep to find a spinning beachball. Firefox was the application in the foreground. Other open apps were Mail, iCal and iTunes. I used "force quit" on Firefox (took several tries) but that didn't resolve the problem. I still had the spinning beachball. I tried to force quit the other open apps, but the computer stopped responding completely and froze. I shut it down and restarted. At first I had a white screen with a beachball, and then got the flashing folder with the question mark in it. I pulled out my "Everything Mac" book and proceeded to try the various steps suggested: 1. Option+ power button: Tried this, got a blank white screen, then the question mark again 2. Tried zapping the PRAM - result was the white screen with question mark again 3. Tried unplugging the machine after shutdown and left it unplugged for a while. No change when I plugged it back in and restarted. White screen with question mark. 4. I have tried disconnecting all peripherals and repeating the above. Would you suggest that I pull out the extra RAM to see if that makes a difference? I have had no signs of RAM-related problems. That is probably my next step. Anything else I should try? Since I cannot even get the computer to boot, I obviously can't try to repair permissions or alter system settings in any way. I had planned to go to the Apple store today anyway to attend one of their seminars. If I need to make a Genius bar appt. and take it in, do I need to remove the extra RAM first? Should I try calling Apple Care first? Does this sound like a problem that will require a reinstall of OS X? Is there any way I would be able to get my data before a reinstall? Thanks in advance for any suggestions for this Mac newbie.