Hello. I own a 20" 2ghz, 2gb, aluminum iMac and I feel it's acting sluggish lately. I have been using Photoshop and Lightroom quite hard since I got my first DSLR and I think this machine should handle to manage those apps quite smoothly at the same time; it doesn't and I have to quit Lightroom and even Photoshop acts a bit slow when working with 100mb and above psd files. Maybe I'm asking too much to this machine and I just need more RAM but I'd like to hear what do you say. Thanks!