How to make Windows XP 32 bit use more than 4GB memory

[echarcha]

Windows XP 32 bit version has, as I understand, a limit of 4GB memory. In reality it seems to use only upto 3GB memory.

I have a new desktop at work for another product development and it has 4GB Ram installed. How can I make Windows XP utitlize all of it. Currently the max it uses is 3GB.

[BABU_HYDERABADI]

Originally Posted by echarcha

Windows XP 32 bit version has, as I understand, a limit of 4GB memory. In reality it seems to use only upto 3GB memory.

I have a new desktop at work for another product development and it has 4GB Ram installed. How can I make Windows XP utitlize all of it. Currently the max it uses is 3GB.

I don't think you can do that bcos for a 32 bit OS the addressing limit itself is 2^32 which is 4 Gig. The only way is move over to 64 bit if your CPU supports it.

[Ravi]

Chapai: XP-32 can actually access entire 4 GB, but not all is available for use. ≈500MB is used for IO devices and other mobo related stuff. Even if you use a XP-64, you're still stuck at 3.5GB max.
If performance is your concern, try upping pagefile to twice size of RAM.

[Budmaas]

Charchu ... . .Why don't you start using vista..... ?


It is better & working fine...no problems.

[Gajodhar]

Only viable option is move over to 64 bit edition. Sadly one cannot upgrade from 32-bit to 64 bit without re-installing windows and formatting the hard drive.

[Mr.Bharat]

Originally Posted by Gajodhar

Only viable option is move over to 64 bit edition. Sadly one cannot upgrade from 32-bit to 64 bit without re-installing windows and formatting the hard drive.

And whenever we format the disc, why do we always looose some amount of Hard Drive space ?

[Gajodhar]

Originally Posted by Mr.Bharat

And whenever we format the disc, why do we always looose some amount of Hard Drive space ?

I don't have a definite answer to that - I believe this is just leftover clutter from windows.

[echarcha]

Our corporate version is still Windows XP 32 bit, so Vista is out of the question. We might go directly to Windows 7 when it is approved by corporate IT.

Well, I will make do with what I have

[Ravi]

Originally Posted by Mr.Bharat

And whenever we format the disc, why do we always looose some amount of Hard Drive space ?

HD makers measure in decimal and not binary. For them 1kb = 1000 bytes, not 1024(actual). So a 320 GB is 320 * (1000^3)/(1024^3) = 298 GB. This is actual size when unformatted. When formatted, different file systems take up their own space for table of contents. That takes up a lot of space, as well. For instance, 'System Volume Information' on an NTFS drive takes up a lot of space. Also, If you have a 1GB file on a drive, the whole file is not contiguously stored. It'll be broken into chunks and spread all over. So you need a place where file system stores pointers to each chunk. That ToC is not available to the user. That's why you see less.

[jana05]

Here is some information. I have no way to confirm this info. I found conflicting info as well...wud recommed more reading before using.

Snippets

Link

Introduction
PAE is an Intel-provided memory address extension that enables support of greater than 4 GB of physical memory for most 32-bit (IA-32) Intel Pentium Pro and later platforms. This article provides information to help device driver developers implement Windows drivers that support PAE.
Microsoft supports Physical Address Extension (PAE) memory in Microsoft Windows 2000, Windows XP, and Windows Server 2003 products:



PAE @ Wiki

In computing, Physical Address Extension (PAE) is a feature of some x86 and x86-64 processors that enables the use of more than 4 gigabytes[1] of physical memory to be used in 32-bit systems - given appropriate operating system support.

..................

x86 processor hardware architecture is augmented with additional address lines used to select the additional memory, so physical address size is increased from 32 bits to 36 bits. This, theoretically, increases maximum physical memory size from 4 GiB to 64 GiB.
...............

Physical Address Extension: PAE is an Intel-provided memory address extension that enables support of up to 64 GB of physical memory for applications running on most 32-bit (IA-32) Intel Pentium Pro and later platforms. Support for PAE is provided under Windows 2000 and 32-bit versions of Windows XP and Windows Server 2003. 64-bit versions of Windows do not support PAE.

More discussions/information here #1 , here #2 and here #3

* Total physical address space is limited to 4 GB on these versions of Windows.
PAE is supported only on 32-bit versions of the Windows operating system.

PseudoCode for Disclaimer:
if (Read_Judge_Use@YourRisk == FAILED) then Sympathy2User("Its_User_Responsibility b'coz Info_4m_Mr.0_in_M$_Tech")
elseif ( Read_Judge_Use@YourRisk == SUCCESS) then SendCompliments("Repped u & SEND MONEY IN $")
(Just for Humor )



Experts on M$, your thoughts are welcome...

[jana05]

Please ignore my previous post. The reason its disabled is bcoz the drivers don't support PAE enabling and more than 4GB. They generally crash the OS. So its disabled.

Thanks for reading...but the discussions provide useful insight...

[jana05]

Originally Posted by BABU_HYDERABADI

I don't think you can do that bcos for a 32 bit OS the addressing limit itself is 2^32 which is 4 Gig. The only way is move over to 64 bit if your CPU supports it.

Good math, but .........

Intel's Pentium pro introduced the PAE mechanism which means 36-bit wide address bus, so 2^36 is greater than 4GB.

4GB hardware limit problem was solved in the year 1995.