Hey all. I recently upgraded my new iMac G5 to 1GB of RAM. Is anyone here familiar with the way OS X uses RAM? Here's why I ask... Just a few minutes ago, I had about 5 apps open (Adium, Acquisition, iChat, Safari, and iTunes), and I had about 700MB of RAM free. I opened Entourage to check my e-mail, and my available RAM went down to 42MB free. Does Entourage use 658MB of RAM? lol What is more weird: After quitting Entourage, my free RAM only went up to about 80MB. Activity Monitor now says I am using 971MB of RAM and have 52MB free. The only apps I have open are Safari, Activity Monitor, Adium, and Acquisition. When I only had 512MB of RAM, I had high RAM pageout numbers, and those numbers have shrunk considerably now that I have 1GB, so I *believe* the extra RAM is helping. But I still have SOME pageouts occurring, and I have no idea why, with so much RAM in my system. I just have no idea why my computer is using 900MB of RAM now that I have 1GB total, and it was only using 400MB when I had 512 total. Why is so much RAM being used now? I was thinking I could expect to have 300-500 MB free most of the time. Edit: By the way, do my Wired, Active, Inactive, and Used numbers mean anything helpful? I have 87 wired, 226 active, 672 inactive, and 985 used now, with 38 free.