Hi , ive asked this question loosely before. but am i able to just buy any DRR2 800 (PC6400) ram? or dose it have to be Mac certified ?? im in need of a quick cheap options of an extra 2gig of ram to tide me over till the summer is out. not looking to pay more than 40 pounds. ive seen alot of branded ram on overclockers.co.uk for around these prices. can i do this or will it cause any issues ? Thank you.