I'm picking out my first mac. I want an all-purpose computer that will have the capacity for light to medium video editing (standard def). I was looking at the base model 20" imac. Would this be sufficient? I'm switching from a very old PC so I'm sure any of the current mac machines would really wow me with their performance. I don't need a monster machine. I don't do any gaming. Also I'm a student so I can get the edu discount. I'm also interested in the refurb imacs. Apple has had a lot of refurbs with ATI graphics cards lately, such as the ATI Radeon Pro or something like that. those cards have dedicated graphics memory as opposed to the current NVIDIAs in the 20" imacs. but those ATI cards are older cards, I'm guessing. So my question is, is an older ATI card with dedicated graphics memory better or worse than a new NVIDIA with shared graphics memory? I'm not really opposed to getting a new or refurbished 24" imac, the one that's the step up from the 20", but I couldn't go any more expensive than that. but 20" of screen space is more than enough for me. Sorry, lots of random thoughts here, but after months of waiting I'm finally getting a mac and I'm very excited! I want to get the best one for my budget but I don't want to be thrifty. I want a machine that will perform well and last 4-5 years.