Why would more RAM of same type/speed not work?

[TylerH]

I know what type of RAM I have: DDR3-PC3 12800 at 1600MHz. My laptop came with 2x4GB and I want to upgrade to 2x8GB and every resource I've found says 4GB per slot (and I only have 2 slots) is the most memory this laptop can use ( http://www.crucial.com/upgrade/Samsung-memory/Series+5/NP550P5C-T01US-upgrades.html ). Why would a 8GB stick of the same type and speed not work? I'm interested in the technical reasons, if anyone has any idea. I like to think I have a good understanding of computer organization, but the idea of two sticks of the same type/speed being incompatible just defies my understanding.

Thanks for your time,
Tyler

 

[Greg Bernhardt]

This may give you some insight as to why chipsets have a hard memory limit and slot limit.
http://duartes.org/gustavo/blog/post/motherboard-chipsets-memory-map

 

[TylerH]

Thanks for the informative link. I knew the logical vs physical addressing thing but not the part about the chipset.
That really sucks though. I was hoping it was some stupid mistake and I would be able to upgrade. But, then again, when, other than compiling GCC and baking fluids in Blender, will I actually use 8GB let alone 16.