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iFixit hails replaceable LPCAMM2 laptop memory as a 'big deal'
(www.theregister.com)
This is a most excellent place for technology news and articles.
It lets you build one motherboard with all possible ram options.
The smallest one has all it ram soldered on. Therefore less time is required in assembling the laptops. All other patients just need the extra ram placed in the dimm slot.