I'm beginning to doubt my purchase of my iMac. I have 1.5 GB of RAM, which I personally installed, and the iMac recognizes it. Right now, I have Finder, Dashboard (NO WIDGETS), Safari, iTunes, and Activity Monitor running. Activity Monitor says I have only 60 MB of free RAM. There is over a GB of "inactive memory". What does this inactive memory do? If it's inactive, why isn't it "free"? Or maybe I'm asking the wrong questions? Is inactive memory memory that isn't being used, or is being used in some other fashion? Because if it's being used, I don't understand how Mac users get by on even 2 GB of RAM... Just as a note, when I restarted the Mac, I had over a gig of free RAM. That's more like it. It usually hovers around 500 or 600 MB free, which is still not much considering how much RAM I have. Could someone shed some light for me on this? [Edit] Checking my Activity Monitor... what's WindowServer? It's taking up the most memory (both physical and virtual) on my Mac. I disabled Windows File Sharing and the process is still there, unless it's something else?