i just bought 2GB of DDR2 667Mhz SO-DIMM PC2-5300 RAM, and when I came to installing it i found it had those black things one both sides instead of just one as was the case for the original 2x256MB sticks!?! i presumed this was because they held 4 times as much memory so didn't think about it too much. Put them in and they were really stiff, then the levers wouldn't take them out again. i managed to get them out by pulling on the RAM with my fingers. After installing the original RAM again (which by the way went in very easily) i restarted my MacBook and got the shock of my life.... the computer was only reading 256MB of RAM!! and was going very slow! i thought i had ruined the slot by putting in wrong RAM, but after an extra 2 more restarts it worked again! so basically, is this RAM ok? is it normal to have the black things on both sides instead of one? I know the RAM has to be 200pin, i don't know how to check it though! All i know is that the RAM is the same size as the previous RAM (dimensionally) sorry if this doesnt make too much sense! its late! thanks in advance i was really scared for 5 minutes or so! i thought i had wrecked my baby!