[coreboot] 8 GB DIMMs on Nehalem (Arrandale)

[Andrey Korolyov]

> Not sure if I interpret "within an entire family" correctly, but the
> online specs for the 820QM are clearly wrong

Yes, this statement is very blurry - I thought about artificial memory
limitations like ones in C2000 Atom server series - there are almost
identical models (C2530 and C2550 for example) which has different
maximum amount of RAM. For Clarksfield web part of ARK is obviously
wrong, as official third-parties like Lenovo stated 16G support, but
datasheet is no better:

"One or two channels of DDR3 memory with a maximum of one SO-DIMM per channel"

which is certainly not related to widely used Clarksfield four-DIMM setup.

> Definitely not worth it for this 7+ year old hardware (unless someone
> has a suitable scope and the knowledge already... the best scope I have
> access to is an Agilent MSO6104A but no idea where to even start - and
> no interposer obviously) but you seem to imply that the 8GB problem is
> an analogous one... do you think about the 16 GB problem as well?
>

I don`t think of this problem as of 'analogous', there`s simply not
enough data to understand the problem. I have 720QM with 32G, but this
laptop hardly could be called portable, perspective of having >8G of
RAM in Arrandale laptops is brilliant. Regarding issue analysis, I
suppose nothing much could be done with *scopes*, because data
exchange violation seem not to be strict and/or large and it is
impossible to catch this one in a sane time without proper bus
analyzer. Speaking for Agilents, only 1690x chassis are capable to
work with analyzer blades suitable for DDR3 analyzer, but they are
somewhat pricey.