I got 2 512mb SODIMMs and a 80gb 7200rpm HDD for my 13" MacBook today. The installation process went fine and the MB works and performs great. I made a strange discovery though when I removed the original 256mb sodimms. Both of the dimms had a couple of very small, almost non-existent smudges of a white creamy material that looks like thermal paste. The smudges were on one side of the dimms only (the one facing upwards when installing them). My temps are generally ok (from what I've read)... I really don't want to know how much thermal paste is in the laptop!