Total memory in XP pro sp3

Bob I wrote:

> Sorry, it's not artificial, its the 32 bit addressing. You have to
> implement addressing extensions if you want a 32 bit system to address
> more than 4 GB of memory addresses.

"addressing extensions" (PAE) is just another way of refer to memory
addresses in a 32bit OS. XP has always supported PAE - it just ignores
anything above 4G, hence it is an artificial limitation.

Prior to SP2, address space above 4G was also supported - until you had
4GB usable RAM.

<want to see the entire conversation, not just this thread? click on the
link below>
http://groups.google.com/group/micro...286a59e5978977
<want to see the entire conversation, not just this thread? click on the
link above>



granjan wrote:
> My friend wants to install an additional 2 GB of memory in her Dell
> XPS 600 which has 2 GB already installed. The manual for her
> computer says it only supports 2 GB for Windows XP SP3 with 32 bit
> system. My Dell Dimension 8400 manual says it supports 4 GB memory
> for Windows XP MCE SP3 with 32 bit. Why do they support different
> amounts of memory?

smlunatick wrote:
> Windows XP Home is limited to 2 GB of RAM (Microsoft's decision.)
>
> Windows XP Professional is supposed to be limited to 4GB of RAM
>
> Windows MCE is a "tweaked" verison of Windows XP Pro for enhanced
> video playing and TV. Since it is based on XP Pro, it gets the XP
> Pro limit.
>
> However, all these different RAM sizes are "moot" since these are
> based on 32 bit processor coding and at most your will get 3.25 to
> 3.5 GB of RAM. This is the extreme limit because of most 32 bit
> processors are limited to this.
>
> (Only the limited Windows XP Pro 64bit can start to use the 4GB of
> RAM. However, support / drivers are very limited.)

dennis wrote:
> It is wrong to blame the CPU. 4GB is an artificial limitation in XP.

Shenan Stanley wrote:
> Some suggested reading:
>
> for dennis:
> http://www.geoffchappell.com/viewer....nse/memory.htm
>
> for smlunatick:
> http://msdn.microsoft.com/en-us/libr...78(VS.85).aspx
>
> general:
> http://blogs.technet.com/markrussino...1/3092070.aspx
> http://www.ofzenandcomputing.com/zanswers/1079
>
> Enjoy.

dennis wrote:
> Yes, I have seen that one before. Why?

Why what?

Why did I actually give people references instead of making a comment and
dashing off?
Why did I seemingly direct one link towards you that seemingly backed up
what you said?
Why did I do the opposite for smlunatick, showing them the error in their
2GB XP Home comment?

Why not? Better to have the information out there than not - and better to
actually share it instead of just indirectly reference it without any
further comment - IMO. ;-)

--
Shenan Stanley
MS-MVP
--
How To Ask Questions The Smart Way
http://www.catb.org/~esr/faqs/smart-questions.html

dennis wrote:

> smlunatick wrote:
>
>> This is the extreme limit because of most 32 bit
>> processors are limited to this.
>
>
> It is wrong to blame the CPU. 4GB is an artificial limitation in XP.

Sorry, it's not artificial, its the 32 bit addressing. You have to
implement addressing extensions if you want a 32 bit system to address
more than 4 GB of memory addresses.