Re: XP And RAM

On Sun, 07 Sep 2008 09:39:09 -0500, JD <JD@xxxxxxxxxxxxxxx> wrote:

I'm using XP home edition with SP3 and I have 4GB of RAM installed. From
previous posts in this newsgroup I learned that 32-bit operating systems
can only address 4GB of RAM.


All 32-bit client versions of Windows (not just Vista/XP) have a 4GB
address space. That's the theoretical upper limit beyond which you can
not go.

But you can't use the entire 4GB of address space. Even though you
have a 4GB address space, you can only use *around* 3.1GB of RAM.
That's because some of that space is used by hardware and is not
available to the operating system and applications. The amount you can
use varies, depending on what hardware you have installed, but can
range from as little as 2GB to as much as 3.5GB. It's usually around
3.1GB.

Note that the hardware is using the address *space*, not the actual
RAM itself. The rest of the RAM goes unused because there is no
address space to map it too.



I found this:

http://support.microsoft.com/kb/929605

It's talking about Vista but I noticed it says:

"WORKAROUND
For Windows Vista to use all 4 GB of memory on a computer that has 4 GB
of memory installed, the computer must meet the following requirements:

The chipset must support at least 8 GB of address space. Chipsets that
have this capability include the following:

Chipsets that support AMD processors that use socket F, socket 940,
socket 939, or socket AM2. These chipsets include any AMD socket and CPU
combination in which the memory controller resides in the CPU.

The CPU must support the x64 instruction set. The AMD64 CPU and the
Intel EM64T CPU support this instruction set.

The BIOS must support the memory remapping feature

An x64 (64-bit) version of Windows Vista must be used."


Even if my AMD AM2 processor and my BIOS meet the above requirements,
I'm still not going to be able to address more than 4GB of memory since
my XP is a 32-bit OS?

--
JD..

--
Ken Blake, Microsoft MVP - Windows Desktop Experience
Please Reply to the Newsgroup
.

Relevant Pages

  • Re: Windows XP Startup
    ... "Terry R." ... I can't stand it how when I boot Windows XP the desktop appears but I'm not able to use it yet 'cause it's still loading my programs and services. ... Strange how the computer I'm using today doesn't make me any more productive than the ones I used back in 1988 with a memory manager and DeskView (386-20 with 2 meg of RAM). ... Other than install more RAM, faster hard drive, and graphics card (assuming you already have a fast CPU), there isn't much left to do, if you've already removed unnecessary items from the Startup Menu, etc. ...
    (microsoft.public.windowsxp.general)
  • Re: Windows XP Startup
    ... "Terry R." ... XP-M 2400+) and the ram is maxed out. ... I can't stand it how when I boot Windows XP the desktop appears but I'm not ... I use Antivir for AV and it doesn't bog the CPU at all. ...
    (microsoft.public.windowsxp.general)
  • Re: Paging File on Second HDD
    ... With an older computer adding RAM can be non-productive. ... CPU involves replacing the motherboard and the cost starts to ... and it plays Windows XP like a fiddle. ... and moving the paging file from the C: ...
    (microsoft.public.windowsxp.perform_maintain)
  • Re: Bios showing wrong CPU
    ... Socket 775 FSB800 CPU. ... the BIOS screen with a message sayinh. ... Oh and taking out the RAM makes no difference - I cannot remember ...
    (uk.comp.homebuilt)
  • Re: KFSN4 malfunction ?
    ... it did not work and the CPU Warning light on the MB indicated that CPU1 was "missing". ... I took it out and installed only the second CPU on CPU1 socket. ... If you suspect your symptoms are purely due to the choice of BIOS ... is to remove all RAM. ...
    (alt.comp.periphs.mainboard.asus)
Loading