Hello LN,
Thanks for the quick response. I reviewed the reference you mention. I don't know if this makes a difference but mine is the 15" with the 2.8 processor. I am not much of a technical person. I'm more of a user. But I did read a response elsewhere that a higher Mhz card would work, but not at the memory card's designed Mhz level - in this case 1066 vs 1866.