Re: XP memory detection problem at 4 GB

Tech-Archive recommends: Repair Windows Errors & Optimize Windows Performance

From: Jim (Jim_at_discussions.microsoft.com)
Date: 08/26/04 

Date: Thu, 26 Aug 2004 08:45:06 -0700

I currently have the exact same problem on 6 XP machines all running 4 GB of
RAM. 5 Show about 3.37 GB of RAM and one shows 3.0 GB of RAM. I am looking
for the registry key in XP to see beyond the 4 GB threshold. That is the
only idea I have to solve the problem so far.
Jim

"Eddie" wrote:

> Hi Bob,
>
> It says 3144948. So it's only showing around 3 GB.
>
> I think this might be related to the memory map. XP only
> sees a 4GB memory map, but my bios has a setting DRAM
> over 4G Remapping. What this seems to do (based on what
> I've seen from running memory diagnostics) is that it
> takes the last GB of 4GB of memory to the map above the
> 4GB boundary. So we have,
> ----------------------
> | 0-3072 | 4096-5120 | equalling 4GB total,
> ----------------------
> instead of,
> ----------
> | 0-4096 |
> ----------
>
> This is why I only see 3GB in XP with this set (i.e. the
> first map section). When I don't have this BIOS setting
> enabled one would think that I would get all four GB
> before the first boundary, but nope, Windows and the
> memory diagnostics see,
> ----------
> | 0-3584 | , so it shows 512MB less than 4GB.
> ----------
>
> I don't know if this is a mobo issue or what, but for
> some reason the full 4GB cannot fit in the first map.
> Has anyone else had any experience with 4GB of memory
> behaving in this way?
>
> I'd appreciate any help,
>
> Eddie
>
>
>
> >-----Original Message-----
> >
> >"Eddie" <anonymous@discussions.microsoft.com> wrote in
> message
> >news:19d101c46f70$b4589120$a601280a@phx.gbl...
> >> Hi Everyone,
> >>
> >> I have an Athlon Fx-53 (939) system with 4GB of dual-
> >> channel memory filling the memory banks of an Asus A8V
> >> motherboard.
> >>
> >> For some reason XP doesn't seem to detect the full 4GB
> of
> >> memory installed. In the System Information tool it
> >> claims a "Total Physical Memory 2048.00MB"
> and "Available
> >> Physical Memory of 2.64GB", which is incorrect (not to
> >> mention seemingly illogical).
> >
> >Right click on the task bar at the bottom of your
> Windows XP
> >screen and click on "Task Manager", then on
> the "Performance"
> >tab. What does it say for "Total" under "Physical
> Memory (K)" ?
> >
> >-- Bob Day
> >http://bobday.vze.com
> >
> >
> >.
> >
>

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