It's probably something in the way your motherboard maps the ram. The top of
the 4 GB address space is taken up by motherboard resources. Some
motherboards try to play tricks with this and remap ram that is trying to
use this space to up above 4 GB. The motherboard resources have to stay
below 4 GB for 32 bit driver compatibility. There may be BIOS settings you
can change that will affect this. Switching to a 64 bit OS may also fix it.
In any case with 4 GB installed in 32 bit Windows you will be lucky to see
more than 3.25 GB reported by Windows.
--
Kerry Brown
Microsoft MVP - Shell/User
http://www.vistahelp.ca
"sjc" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> If I install 4G of RAM I get the following:
>
> The My Computer | Properties | General shows 2G of RAM
> and the System Information shows:
> Total Physical Memory 4,096 MB
> Available Physical Memory 1.7 GB
>
> If I install 3G of RAM I get the following:
>
> The My Computer | Properties | General shows 3G of RAM
> and the System Information shows:
> Total Physical Memory 3,072 MB
> Available Physical Memory 2.7 GB
>
> WIth 1G less RAM the Available Physical Memory increases by 1G.
>
> My hardware is a Core 2 Duo 6600 and the Intel 975 chip set with XP Pro
> SP2.
>
> What's going on here? Does XP do better with 3G then 4G. I have tried
> boot.ini switches /3GB /PAE which have no effect.
>