Installed memory today, questions immediately

Robert Bonomi bonomi at
Sun Nov 7 16:34:21 UTC 2010

> To: "FreeBSD Mailing List" <freebsd-questions at>
> Date: Thu, 04 Nov 2010 19:13:53 -0700
> From: "justin v" <vic at>
> Subject: Installed memory today, questions immediately
> I installed 4GB or memory today.  I rebooted and see this, the first line  
> after the splash menu thing:
> 983040K of memory above 4GB ignored
> dmesg shows avail mem amount and I am concerned as well:
> real memory  = 4294967296 (4096 MB)
> avail memory = 3139940352 (2994 MB)
> is a stick bad perhaps?

Looking at this a little more carefully, the memory itself is fine
The problem is _where_ it is being mapped into the address-space at.

The first line is the give-awy  ".... above 4GB ignored."

At this point I'm *guessing*, but it looks like 'main memory' is gettnig 
mapped into the address-space in 1gb chunks and there is "something" 
(probably video memory)   occuping space up to 0x?38000000    maybe a 
128mb video card mapped in at a base 768mb

If there is a way to relocate where the (presumed video) memory is mapped,
say, down to a bae of 128mb, you could potentialy pick up 640 megs of
usable memory.  giving 3-3/4 gig less a bit, instead of barely 3 gigs.

It's worth checking the video board manual and/or 'configuration' utility
for a tweak.

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