I just added my new ram 4x2 gigs for a total of 10 with the 2 gigs already in place. My first try made the computer detect 6 gigs, I left the Apple ram in the slots they were in then added equally the other sticks in the next slots (2-3 on each side). Unplugged everything, opened it again and moved the third party memory to 1 & 2 and took the Apple memory from slot 1 to slot 3. Restarted the computer and now it detects 8 gigs. Improvement... but there is still an unnoticed 2 gigs somewhere. Anyone!?