Dear all. My question is about upgrading my mac pro Dual Core 2.66 with more ram +- 2 gig more! Now I have 2 gig (512 x4) on the 2 slots! What can I do with this configuration and keep the 256bit sream? What type of ram need I? Where to buy? Is there somewhere a visual explanation how to do about it? Regards and thanks, Trogledyte Mac.