Windows Server 2008 64-bit Only 3.75Gb RAM Usable

Hopefully a quick question: I am running Windows Server 2008 R2 Enterprise
64-bit on a Dell PowerEdge server. I have 4Gb RAM installed in matched pairs
(2 x 2 x 1Gb). The BIOS is happy that I have 4Gb RAM installed, and the
Windows Memory Diagnostic tool is happy too.

The problem is that Windows reports 4.00 Gb (3.75 Gb usable). So my question
is: where has the rest gone? Why isn't all 4 Gb usable?

TIA

Charles

Am Tue, 27 Jul 2010 12:37:18 +0100 schrieb Charles:

> The problem is that Windows reports 4.00 Gb (3.75 Gb usable). So my question
> is: where has the rest gone? Why isn't all 4 Gb usable?

Your bios must support memory remapping.
PCI extensions use the adresse from 3.75 GB to 4.00 GB and you can only use
the RAM in the space if it's mapped beyond 4.00 GB.

greetings
Carsten
--
ID = 0x2BFBF5D8 FP = 53CA 1609 B00A D2DB A066 314C 6493 69AB 2BFB F5D8
http://www.realname-diskussion.info - Realnames sind keine Pflicht
http://www.spamgourmet.com/ + http://mailcatch.com/ - Antispam
cakruege (at) gmail (dot) com

Hi Carsten

Thanks for the reply. I don't recall seeing anything about remapping on the
BIOS setup page but I'll double-check. I know that the server can only take
up to 4Gb RAM, so perhaps that means I won't be able to remap above that
anyway.

Charles


"Carsten Krueger" <> wrote in message
news:...
> Am Tue, 27 Jul 2010 12:37:18 +0100 schrieb Charles:
>
>> The problem is that Windows reports 4.00 Gb (3.75 Gb usable). So my
>> question
>> is: where has the rest gone? Why isn't all 4 Gb usable?
>
> Your bios must support memory remapping.
> PCI extensions use the adresse from 3.75 GB to 4.00 GB and you can only
> use
> the RAM in the space if it's mapped beyond 4.00 GB.
>
> greetings
> Carsten
> --
> ID = 0x2BFBF5D8 FP = 53CA 1609 B00A D2DB A066 314C 6493 69AB 2BFB F5D8
> http://www.realname-diskussion.info - Realnames sind keine Pflicht
> http://www.spamgourmet.com/ + http://mailcatch.com/ - Antispam
> cakruege (at) gmail (dot) com