On Tue, 8 Jan 2008, Brian Weeden wrote:
Yeah it's nothing to worry about. Basically, instead of trying to
explain to people why 32-bit CPUs can't use more than 4GB and windows
in particular can't address more than 3.2 GB (which even I don't fully
understand) they just use the term "designed for 64-bit". Just
marketing slang.
The reason is backwards compatability!
32 Bit Addressing can only support 4GB of memory, but the way addressing
is used on 32 bit systems that means ALL TYPES of memory. Video card,
SCSI card, etc. Anything with memory will use up some of that addressing
on a 32 bit system.
Just like Video cards, etc. would claim memory in the region between 640K
and 1024K on old DOS systems, video cards writted after the 32bit
changeover claimed memory at the top of the 4GB barrier and move down.
If you have an SLi pair of cards with 512MB each, you're limited to 3GB of
system memory addressable without a special motherboard that will adjust
your memory mappings.
More information can be found:
http://www.dansdata.com/askdan00015.htm (Great link explaining it)
http://blogs.msdn.com/hiltonl/archive/2007/04/13/the-3gb-not-4gb-ram-problem.aspx
Christopher Fisk
--
Mal: "Using corpses for smuggling is a time-honored repulsive custom."
Jayne: "Maybe it's gold!"
Zoe: "And maybe this was a friend of ours, and you wanna show a little respect."
Jayne: "I got respect. But I'm just saying... gold!"
