So I've found RAM on Newegg.com but don't know the exact kind to buy. I want to save when I buy my iMac by keeping the original 2x1gb sticks in it and buying the 2x2gb sticks elsewhere. I know it must be 800mhz DDR2-SDRAM PC2-6400. Other than that, what brand should I buy? I've found some for around $80 which is much cheaper than the $200 Apple charges for the upgrade. Hold on, now I found something called "Fully Buffered" memory for Macs on the same New Egg site. They sell for more than the memory upgrade from Apple. What gives? Is the cheap stuff worth the savings? Is this more expensive FB stuff worth the extra money? What about Kingston 4gb DDR2 800 (PC 6400) Dual Channel Kit Memory for iMac? KTAMB800K2/4GB $82.69 free shipping. Sounds good but will it work as well as factory installed Apple 4gb? And then what do I do with the old memory?