I'm getting the 20" iMac and will break it in this weekend for a DJ gig running MegaSeg software controlling access to 12,000 songs (100 GB) stored on the iMac hard drive. Is 512MB of RAM enough to run that and iTunes just for this gig? I'd like to run it as is this weekend and then upgrade when I have more time. I DJ'd a gig a couple of months ago with my PowerBook with 512MB of RAM. I'd just upgraded to 10.3.9 and got a bunch of spinning beachballs which caused audio glitches. Not good through a loud PA. It ran fine before the OS upgrade.