I recently purchased a Santa Rosa MacBook (white 2.2GHz) and upgraded the ram to 4GB total.
I did this at 2 different times.
I used the macbook as it shipped with 2 x 512MB chips for a week... then upgraded the one in slot 0/0 to 2GB and left the one in slot 1/1 as 512MB (2.5GB total) when I removed the stock 512 chip... i noticed the pins on this chip appeared to be corroded a bit... or at least it looked like it was... the gold pins were covered in a white color.
I decided to upgrade the other chip today and when I removed it... it looked the same way as the other one.
Is this normal, does Apple put some kind of chemical on the pins for better contact or something (so their tech's can tell when the user has removed the ram if there is a warrantee issue)? Or is this a problem?

I did this at 2 different times.
I used the macbook as it shipped with 2 x 512MB chips for a week... then upgraded the one in slot 0/0 to 2GB and left the one in slot 1/1 as 512MB (2.5GB total) when I removed the stock 512 chip... i noticed the pins on this chip appeared to be corroded a bit... or at least it looked like it was... the gold pins were covered in a white color.
I decided to upgrade the other chip today and when I removed it... it looked the same way as the other one.
Is this normal, does Apple put some kind of chemical on the pins for better contact or something (so their tech's can tell when the user has removed the ram if there is a warrantee issue)? Or is this a problem?