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Windows Xp W/ 4Gb Memory?


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I know that XP won't recognize 4gb of memory, but my question is: If I use 2 - 2gb sticks of memory (dual channel) in this motherboard with XP as the installed OS, will XP use the maximum amount of that 4gb that it is capable of recognizing (I believe the max XP 32-bit can recognize is 3.5gb if I'm not mistaken)?

 

Motherboard: http://www.newegg.com/Product/Product.aspx?Item=N82E16813131232

 

Memory (x2): http://www.newegg.com/Product/Product.aspx?Item=N82E16820231121 -kd5-

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You can put 4 gb in XP 32 but the O.S. will only recognize 3-3.5 gb memory. It will still operate

 

 

There is a thing involving the use of PAE to use the whole 4gb? I'll have to research on that one because I can not recall what it was

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You can put 4 gb in XP 32 but the O.S. will only recognize 3-3.5 gb memory. It will still operate

 

 

There is a thing involving the use of PAE to use the whole 4gb? I'll have to research on that one because I can not recall what it was

 

Thank you Joe! -kd5-

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To explicitly enable PAE, use the following BCDEdit /set command to set the pae boot entry option:

 

bcdedit /set [{ID}] pae ForceEnable

 

IF DEP is enabled, PAE cannot be disabled. Use the following BCDEdit /set commands to disable both DEP and PAE:

 

bcdedit /set [{ID}] nx AlwaysOff

bcdedit /set [{ID}] pae ForceDisable

 

Windows Server 2003 and Windows XP/2000: To enable PAE, use the /PAE switch in the Boot.ini file. To disable PAE, use the /NOPAE switch. To disable DEP, use the /EXECUTE switch.

Assume you are dealing with a novice when it comes to entering commands of this type, if I am dealing with the typical everyday ordinary Windows XP Home Edition, 32-bit OS, exactly what would I enter where? I see the command bcdedit /set [{ID}] pae ForceEnable and I wonder if I'm supposed to change anything where it says [{ID}], and do I enter that command at the Start, Run box? I also see "To enable PAE, use the /PAE switch in the Boot.ini file", and I wonder exactly how, if, and where I'm supposed to enter that. M$ isn't being real easy for the novice to understand. Can anyone help with that?

 

Thanks, -kd5-

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The eHow instructions look simple enough, thank you! One question: On my computer the /noexecute switch reads noexecute=optin, I'm assuming the /pae would go at the end of that so the complete line which currently reads

multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Home Edition" /noexecute=optin /fastdetect

 

would now read

multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Home Edition" /noexecute=optin /pae /fastdetect

 

Just want to be certain... :blushing: -kd5-

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When you enable Data Execution Prevention (DEP), Windows automatically

enables PAE. When you disable DEP, Windows automatically disables PAE. For

more information, see /noexecute.

 

Example

multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Windows Server 2003,

Enterprise" /fastdetect /pae

 

http://msdn.microsoft.com/en-us/library/ff557168%28v=VS.85%29.aspx

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In Windows XP Home Edition there are only 2 options regarding DEP: Enable for essential Windows programs & services only (selected by default), or enable for ALL programs & services except for those I select. Without an option to disable DEP, it is on by default. So according to that article PAE is also enabled by default?

 

I wish M$ was clearer than mud. -kd5-

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Bear in mind that very few consumer-grade programs are designed to utilize more than 2GB of the 4GB virtual address space.

 

Enabling the PAE extension in XP will allow it to use all the memory available.

Microsoft supports Physical Address Extension (PAE) memory in Microsoft Windows 2000, Windows XP, and Windows Server 2003 products:

 

(Operating system

Maximum memory support with PAE)

 

Windows 2000 Advanced Server

8 GB of physical RAM

 

Windows 2000 Datacenter Server

32 GB of physical RAM

 

Windows XP (all versions)

4 GB of physical RAM*

 

Windows Server 2003 (and SP1), Standard Edition

4 GB of physical RAM*

 

Windows Server 2003, Enterprise Edition

32 GB of physical RAM

 

Windows Server 2003, Datacenter Edition

64 GB of physical RAM

 

Windows Server 2003 SP1, Enterprise Edition

64 GB of physical RAM

 

Windows Server 2003 SP1, Datacenter Edition

128 GB of physical RAM

 

* Total physical address space is limited to 4 GB on these versions of Windows.

 

REF: www.microsoft.com/whdc/system/platform/server/pae/paedrv.mspx, updated February 9, 2005.

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Bear in mind that very few consumer-grade programs are designed to utilize more than 2GB of the 4GB virtual address space.

 

 

I can swallow up 4 gigs of ram pretty quickly, in a matter of minutes. Bear in mind that there are a hell of a lot of people out there that do much more then stare at facebook. A lot of people are still using their computers for actual work, and or just hobbyist who enjoy working with video and graphics.

 

The past two weeks there my computer was using just about every meg of ram in it almost constantly. So much so that I am considering upping it from the 4 gigs that is in it to 8 gigs. If I do nothing would make me happier then to check my system monitor and see all 8 gigs being used :tup:

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I can swallow up 4 gigs of ram pretty quickly, in a matter of minutes ... The past two weeks there my computer was using just about every meg of ram in it almost constantly. So much so that I am considering upping it from the 4 gigs that is in it to 8 gigs

Bruce, this thread concerns Windows XP 32-bit, not other OSes that can address more than 4GB of memory.

 

The remark "few ... programs are designed to utilize more than 2GB of the 4GB" does not imply that programs share a single 2GB area. Each program is allocated its own virtual address space.

Edited by TomGL2
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  • 2 months later...

OK, I've built the computer that has 4gb of RAM installed, XP Home (32-bit) only sees 3.25gb of it. The Ehow instructions do not work, entering /pae at the end of the noexecute=optin switch is not allowed, and no one ever explained what the [{ID}] in the bcdedit /set [{ID}] pae ForceEnable command (c/o the Microsoft article)) is supposed to consist of.

 

The boot.ini on this XP install reads:

 

multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Home Edition" /fastdetect /noexecute=optin

 

As you can see, the fastdetect and noexecute switches are reversed on this windows install, not sure if that means anything. When I try to reverse them to match how it reads on my computer, I get the message "Cannot create the C:\boot.ini file, Make sure that the path and filename are correct.

 

Still not entirely sure if I'm supposed to enter /pae at the end of the entire switch noexecute=optin (according to the Ehow document). Regardless, I get the same "Cannot create..." message.

 

These people aren't very clear in their instructions, regardless of what I do, this windows install won't allow it. The Ehow document acts as if there might be a choice as to whether DEP is enabled or not, XP home only has the 2 options, and they both have DEP enabled by default with no option to disable. That's fine, DEP needs to be enabled, but why would Ehow even suggest there is a choice?

 

According to M$, Windows XP 32-bit is supposed to support 4gb of memory, but why does XP not allow/report the entire 4gb if it's supposed to support it?

 

 

 

 

Can anyone help with this? -kd5-

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Did you run the command in a console

Thanks for responding Bruce, but assume I don't entirely know what "in a console" means (which would be an understatement)... :blushing: -kd5-

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BCDEdit is not appropriate for or included in XP.

 

Log on to an account with administrator's rights.  Click Start, right-click My Computer, and click Properties.  Click Advanced.  Under Startup and Recovery, click Settings.  Click Edit.

 

Make the desired changes, then click File, Exit and Yes.  Click OK and OK.

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I managed to get the /pae switch at the end of NoExecute=Optin (NoExecute=Optin /pae) and saved so it now appears whenever you look at boot.ini, rebooted, Windows XP still reports 3.25gb of the 4gb of RAM installed.

 

This is ridiculous. Even M$ states XP should handle 4gb of RAM, so why can't I get XP to see it????? -kd5-

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Enabling PAE

To enable PAE:

 

•Locate the Boot.ini file, which is typically in the root folder (for example, C:/) and remove its Read-Only and Hidden attributes.

 

•Open the Boot.ini file with a text editor, and then add the /PAE parameter to the path, as shown in the following example:

 

[boot loader]

timeout=30

default=multi(0)disk(0)rdisk(0)partition(2)\WINDOW S

[operating systems]

multi(0)disk(0)rdisk(0)partition(2)\WINDOWS="Microsoft Windows XP Professional" /noexecute=optin /fastdetect /PAE

 

 

http://www.microsoft...pae/paedrv.mspx

Edited by Bruce
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multi(0)disk(0)rdisk(0)partition(2)\WINDOWS="Microsoft Windows XP Professional" /noexecute=optin /fastdetect /PAE

That's exactly how this reads except where yours says partition(2), this says partition(1), (and Professional is Home Edition) and Window's System Properties still reports only 3.25gb of RAM. -kd5-

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Windows XP still reports 3.25gb of the 4gb of RAM installed... XP should handle 4gb of RAM

This is normal behavior. XP 32-bit can access a 4 GB address space, but not all of that space is available to address RAM.

 

While earlier Intel processors accessed hardware via port-mapped I/O (PMIO), a memory-mapped I/O (MMIO) architecture is now used. In MMIO, a device's inputs, output, status and control registers, etc., are connected to the memory bus and assigned a specific address range. When both RAM and a device occupy the same address, the hardware has priority and the RAM is nonfunctional at that location.

 

Since hardware is mapped from the top of the 4GB address space and extends to lower addresses, the upper range is not available for RAM, so part of 4GB of RAM effectively doesn't exist.

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