Re: 4 GB or only 3 GB of RAM.
From: kermit (cku192_at_yahoo.com)
Date: Fri, 04 Mar 2005 23:53:25 +0300
> I recently installed Slackware 10.1 with the 2.6.10 kernel on a 32-bit
> (Pentium 4) machine with 4 GB of RAM. The kernel is configured with
> high memory support (4 GB). When I take a look in /proc/meminfo (or run
> top), only (approximately) 3 GB is reported under Mem. I also
> configured the kernel with support for 64 GB of RAM but it didn't
> change anything. Is this normal behavior?
Part of memory may be reserved to map PCI cards memory regions. Some BIOSes
offer something like "Remap PCI memory gap" which effectively makes this
memory available at addresses above 4GB, in which case you need PAE support
(i.e. 64GB RAM support).