Ramjet (http://www.ramjet.com) now offers the ability to upgrade the
older black or white plastic MacBook and metal bezel MacBook Pro to
6B of memroy.
The company offers a 4GB SO-DIMM single module for US$199. This
module can be installed along with a 2GB module ($75) to reach the
system maximum of 6GB. Compatible models of MacBook have the Model
Identifier of 4,1, and compatible MacBook Pros have a Model
Identifier of 3,1 or 4,1. The Model Identifier can be found in your
Apple System Profiler.
These modules are fully compatible with the latest Apple firmware,
and are SPD configured for the MacBook and MacBook Pro. The Ramjet
4GB SO-DIMM single modules are shipping now, and come with a lifetime