I bought a new 08 imac the other day, instead of shelling out the loot for a 4gb version i bought the 2gb however I want to have 4gb of ram. I figured I could find it elsewhere online. I came across this on newegg: http://www.newegg.com/Product/Product.aspx?Item=N82E16820134671 however its rated a bit lower then the specs of the imac which are pc 6400 800mhz. I was wondering if I would notice or have a decrease in performance due to the lower mhz of the memory and or if this memory would even work with a desktop, it seems like a great price but I think its for a lappy, no? Thanks in advance.