BioStar Motherboard eaten my RAM ???!!

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Hello all !

Just recently I upgraded my PC to 4GB of DDR2 RAM --- 2 X 2GB DDR2 RAM

But when I plugged in the memory modules and powered up my PC, I got
an unpleasant surprise !!

Somehow the 4GB of RAM only shows up as 3587072K of Memory !! That's a
whooping 600MB of memory ****missing**** !!!

The motherboard for my PC is Biostar's P4M890-M7-SE and so far it
hasn't given me any problem.

The motherboard has a built-in vga, which I use. I allocate 16MB of
RAM as "shared memory" for VGA, and the "AGP-Aperture" I give it 32MB,
all min figure.

When I first built the PC, I used a 1GB DDR2 memory module. The mobo
showed me the correct mem figures, ie., 1GB (1024MB) MINUS the 16MB
(of shared memory) and a 1MB of "T-Seg memory".

When I purchased a second 1GB DDR2 memory and plugged it in, again the
mobo didn't give me any problem. It correctly gave me the 2GB (2048MB)
MINUS the 17MB of shared and T-Seg memories.

However, when I plugged in the recently purchased 2 X 2GB DDR2 mem
modules, the problem occurred !!

Instead of giving me 4GB (4096MB) MINUS 17MB, all I got is 3587072K
(around 3.42GB) of memory, plus the 17 shared and "T-Seg" memories.

What's going on???

What can I do to get back the 600MB of my RAM that is
****MISSING**** ????


Thank you !!

Re: BioStar Motherboard eaten my RAM ???!!

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It's normal for a 32-bit system.

Re: BioStar Motherboard eaten my RAM ???!!

In article <353c0ef0-43ce-484c-881f-d2c7f88609e3>, Paul Montgomery says...
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Stupid shit...that's the POST amount he's showing and its got fuck all  
to do with 32bit.


I only please one person per day. Today is not your day. Tomorrow isn't  
looking good either. - Scott Adams

Re: BioStar Motherboard eaten my RAM ???!!

In article <353c0ef0-43ce-484c-881f-d2c7f88609e3
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Its got everything to do with it being a 32bit system. A 32bit system has a  
4GB address space. Out of that address space comes all memory mapped  
devices, the largest of which is normally the graphics card. For example if  
you had a 512MB graphic card then that would leave just 3.5GB of address  
space for the RAM. (I think the OP stated he was using 16MB of shared memory  
which would indicate that the graphics card isn't the main culpret.) There  
are other devices which also have to fit into the address space, all of  
which reduce the addressable range left for the RAM. So its normal to expect  
to see only about 3.5GB of RAM even though the system has 4GB of RAM  
installed. Looking at Paul's post, all of this and more is covered in the  
link he provided.

This will affect both the memory reported by Windows and the memory reported  
by the BIOS (at POST) - although presumably some BIOSs may report the full  
amount, just checking and the one I just looked at reports 3327M on a 4GB  

There is a work around (on Windows) to access the remaining RAM, its known  
as Physical Address Extension. I suggest the OP researches PAE. Basically it  
takes advantage of the fact that the all modern PCs are actually running on  
64 bit hardware even if the OS is only 32bit. The following article should  
be a good starting point:
Brian Cryer

Re: BioStar Motherboard eaten my RAM ???!!

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Careful there - even the 386 had a 64Gb logical address space,
although admittedly it could only be directly connected to 4Gb
physical memory.  Using this logic the 286 and predecessors would
have been limited to 64Kb memory as 16 bit machines.

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PAE predates x86-64 - it was introduced with the Pentium Pro.  It
isn't Windows-only either.  What you lose is the flat memory model
since 32 bits can't directly address more than 4Gb memory, at least
on a byte-addressed architecture.  However, the OS can hide much
of the muckiness from an application perspective provided no single
app needs more than 4Gb memory.  If that doesn't hold things get
more interesting.  It is essentially similar to the segment:offset
idea used to get the old 16 bit machines to address 1Mb memory.
Andrew Smallshaw

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