I want to upgrade the iMac I'll be getting to 8GB RAM, and a 2TB Harddrive. I've been looking around, and can get the HD for about 130 pounds (200 for apple upgrade - suppose I could sell the standard 1TB as well), and crucial has the memory for half price. I've changed ram & HD's in a laptop, as well as built my own PC years ago, but never tinkered with an iMac. The main thing that mortifies me is getting dust behind the screen. What is the chance of this happening? As I understand it, I need some sort of suction holders to take the screen off. Where can I get these? And finally, on a side note, if I order with the standard 4GB kit, will I have space for a 2x2GB kit and will i affect performance having non-matched pairs? I'm not sure whether I should save a few pounds and do it myself or play it safe - I'm not sure if it voids my warranty, putting my own stuff in. I'm buying this iMac out of necessity and am scraping the bottom of the bowl to come up with the funds, so every bit helps. Thanks for your input!