Only half of RAM detected on MSI P55-GD65

[blu-Z8efaSeK1ezqlBn2x/YWAg at public.gmane.org (Edward Ned Harvey)]

> From: discuss-bounces-mNDKBlG2WHs at public.gmane.org [mailto:discuss-bounces-mNDKBlG2WHs at public.gmane.org] On Behalf
> Of Rich Braun
> 
> 1) In dual-channel RAM config (sockets 1/3 populated), it only recognized
> 4GB out of the 8GB of RAM
> 
> BIOS splash-screen and other
> menus report all the RAM I installed, but Linux uses only half the
available
> amount, whether I install 2 modules or 4; there is a lot of chatter online
about
>
> What would y'all do about this?  Take the whole thing into Microcenter and
> say "debug this"?  (Hah.)  Or just toss the mainboard into the basement
parts
> bin and start over, like I'm now inclined to do?

* Double check the manual for compatible memory types.
* Look in bios for memory redundancy.
* Buy a different brand memory (many standard parts still suffer
incompatibility issues)  I've seen things like that a lot with custom build
"standard" machine.
* Get a later kernel...  The latest kernel ... Or a completely different
non-linux OS, and see if problem persists.