perhaps the /pae
switch might provide
be of benefit:

http://msdn2.microsoft.com/en-us/library/aa366718.aspx

--

db·´¯`·...¸><)))º>

"MPH-101" <MPH-101@discussions.microsoft.com> wrote in message
news:ED073CDD-AAE2-4C34-92D7-3A44F3BD43F3@microsoft.com...
>I have an HP system running Windows XP Media Center Edition 2002 (SP2) that I
> recently upgraded the RAM on since many of my applications and simple
> Internet activities where thrashing the harddrive to death (I only had 512MB
> of RAM before the upgrade). I now have 4GB of DDR2 RAM and the HP system
> software recognizes all 4GBs of physical memory, so the installation is OK.
> However, Windows only recognizes 3.11 GB. My system has a 3.06 GHz Pentium 4
> CPU, for what that's worth. Many years ago when I used to really get into
> operating system design, and the like, I used to have to create workarounds
> with the memory limitations of MS-DOS and early versions of Windows (e.g.,
> the old 512k limit in DOS and, hence, Windows 3.1). I have now evolved into
> mostly a user these days and do not understand the newer versions of Windows
> like I did the older versions. Am I up against a memory limitation with XP?
> If so, is there a workaround that will allow me to use all 4GBs of RAM? Or
> will I have to upgrade to Vista (yuk!)? Thanks for whatever assistance
> anyone can provide.............