4GB of RAM tunning in windows xp professional xp sp2 with 32bit

[Yman]

Hi,
I 'm running windows XP SP2 on thinkcentre M55 with Intel Core 2 Duo E6550
@2.33GHZ. I'm trying to tune the memory on windows xp sp2 so I can have 4 GB
of RAM.
I can see the 4GB of RAM in the Bios, but windows can't see it because it's
32 bit. I found articles with Microsoft so you can tune the memory. I
followed the documentation and modified the bootini. I didn't have much luck
I can only see 3GB in window mean while 4GB in the BIOS.

This is the bootini "multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft
Windows XP Professional" /fastdetect /PAE /3GB /Userva=2900
/NoExecute=OptOut".

Any Idea, note the machine supports DEP.

 

[Jim]

Hi,
I 'm running windows XP SP2 on thinkcentre M55 with Intel Core 2 Duo E6550
@2.33GHZ. I'm trying to tune the memory on windows xp sp2 so I can have 4
GB
of RAM.
I can see the 4GB of RAM in the Bios, but windows can't see it because
it's
32 bit. I found articles with Microsoft so you can tune the memory. I
followed the documentation and modified the bootini. I didn't have much
luck
I can only see 3GB in window mean while 4GB in the BIOS.

This is the bootini
"multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft
Windows XP Professional" /fastdetect /PAE /3GB /Userva=2900
/NoExecute=OptOut".

Any Idea, note the machine supports DEP.

You cannot access the full 4GB because Windows uses memory mapped i/o. This
unavailable 1 GB overlaps the i/o devices hence it cannot be used.
Jim

 

[Yman]

Thanks,

So there's no way I can do this, I picked up this article from Microsoft Web
Site

http://support.microsoft.com/default.aspx?scid=kb;en-us;291988

 

[Patrick Keenan]

Hi,
I 'm running windows XP SP2 on thinkcentre M55 with Intel Core 2 Duo E6550
@2.33GHZ. I'm trying to tune the memory on windows xp sp2 so I can have 4
GB
of RAM.
I can see the 4GB of RAM in the Bios, but windows can't see it because
it's
32 bit.

Not exactly. Windows can see it, it just won't let you use most of the
last gig because it uses it for system devices.

You will *not* get to use all 4 gig as user memory.

I found articles with Microsoft so you can tune the memory. I
followed the documentation and modified the bootini. I didn't have much
luck
I can only see 3GB in window mean while 4GB in the BIOS.

Then you've pretty much "tuned" it as much as possible.

This is the bootini
"multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft
Windows XP Professional" /fastdetect /PAE /3GB /Userva=2900
/NoExecute=OptOut".

Any Idea, note the machine supports DEP.

You have already achieved your goal, as far as it is attainable. If you
want to use more memory, you'l l need a 64 bit OS.

HTH
-pk

 

[Ken Blake, MVP]

Hi,
I 'm running windows XP SP2 on thinkcentre M55 with Intel Core 2 Duo E6550
@2.33GHZ. I'm trying to tune the memory on windows xp sp2 so I can have 4 GB
of RAM.
I can see the 4GB of RAM in the Bios, but windows can't see it because it's
32 bit. I found articles with Microsoft so you can tune the memory. I
followed the documentation and modified the bootini. I didn't have much luck
I can only see 3GB in window mean while 4GB in the BIOS.

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.

 

[Yman]

Thanks

I will be glad if I can get the machine to show 3.5GB of RAM. Is there any
other way than editing the Boot.ini ??

 

[Yman]

Thanks,

I've tried only the /3GB switch, I only can see 3GB of RAM on the System
Properties.

 

[John John (MVP)]

Hi,
I 'm running windows XP SP2 on thinkcentre M55 with Intel Core 2 Duo E6550
@2.33GHZ. I'm trying to tune the memory on windows xp sp2 so I can have 4 GB
of RAM.
I can see the 4GB of RAM in the Bios, but windows can't see it because it's
32 bit. I found articles with Microsoft so you can tune the memory. I
followed the documentation and modified the bootini. I didn't have much luck
I can only see 3GB in window mean while 4GB in the BIOS.

This is the bootini "multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft
Windows XP Professional" /fastdetect /PAE /3GB /Userva=2900
/NoExecute=OptOut".

Any Idea, note the machine supports DEP.

Windows XP doesn't fully support PAE and the 4GT RAM Tuning doesn't
really have anything to do with physical memory (RAM), it affects how
the Virtual Address Space is alloted between user mode processes and the
kernel-mode components, you should remove these switches from the
boot.ini file. Due to hardware addressing needs Windows XP 32-bits
cannot fully utilize 4GB of RAM and there is no way to overcome the
limitation.

John

 

[Yman]

Thanks,

How about if you have Qautro Process on windwos XP SP2 ?? will that work ?

 

[John John (MVP)]

With Windows XP 32-bits there is *no* *way* to overcome the limitation.
You should only use the /3GB switch if an application vendor instructs
you to do so, using this switch can starve the operating system of
needed virtual memory and it will do absolutely nothing to help you
access the unavailable RAM.

John

 

[Ian D]

PAE is not for Windows XP so get rid of that. Only leave the /3GB
switch. I would also ditch the /USEVA switch too. Only specific
applications installed would require you to need that switch and the
parameters following it. Do more research on Google for this.

- Thee Chicago Wolf

The purpose of the /userva switch is to provide sufficient memory
address space for the XP kernel if the /3GB switch is used. The /3GB
switch adds 1GB to the default 2GB of application memory address
space at the expense of the OS kernel. If Task Manager showed 3.5GB
of physical memory you would be okay, as 0.5GB would be available
for the OS. If Task Manager only showed 3.1GB as available, XP
would only have 100MB, which could lead to a lot of OS paging, or
a system crash. That's why MS recommends a /userva in the range
of 2800 - 2900 MB. The /userva switch gives some memory back to
to OS that is taken by the /3GB switch.

In addition, the extra 1GB provided by the /3GB switch can only
be used by applications that are large address aware, such as
Adobe Photoshop, or Photoshop Elements.

 

[Tim Slattery]

PAE is not for Windows XP so get rid of that. Only leave the /3GB
switch.

No, don't. The 3/GB switch affects the way that the virtual memory
spaces are divided between the OS and the application, it has NOTHING
to do with physical memory. Using /3GB will squeeze the OS into 2GB of
each virtual memory space. Very few apps will need that, and it will
hurt performance.

 

[Jim]

Thanks,

I've tried only the /3GB switch, I only can see 3GB of RAM on the System
Properties.

The /3GB switch only allows you to use 3GB of virtual address space. The
remaining 1 GB is used to map Windows into your virtual address space.
The switch does not affect the amount of RAM that Windows can use.
Jim

 

[N. Miller]

Hi,
I 'm running windows XP SP2 on thinkcentre M55 with Intel Core 2 Duo E6550
@2.33GHZ. I'm trying to tune the memory on windows xp sp2 so I can have 4 GB
of RAM.
I can see the 4GB of RAM in the Bios, but windows can't see it because it's
32 bit. I found articles with Microsoft so you can tune the memory. I
followed the documentation and modified the bootini. I didn't have much luck
I can only see 3GB in window mean while 4GB in the BIOS.

This is the bootini "multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft
Windows XP Professional" /fastdetect /PAE /3GB /Userva=2900
/NoExecute=OptOut".

Any Idea, note the machine supports DEP.

A lot depends upon the way the vendor set up the computer. I have an HP
Pavilion m7590n, MS Windows MCe 2005, SP3. It came with 2GB of RAM and SP2.
When I finally got around to throwing in more memory, I did absolutely
nothing, other than plugging in the RAM modules. I was expecting no more
than 3.1GB, based on my research. Whatever HP did, the System Properties
shows 3.5GB of RAM present; best anybody can hope for. Short of changing
your motherboard, I don't think there is anything you can do to max your RAM
beyond your current level.

 

[John John (MVP)]

The purpose of the /userva switch is to provide sufficient memory
address space for the XP kernel if the /3GB switch is used. The /3GB
switch adds 1GB to the default 2GB of application memory address
space at the expense of the OS kernel. If Task Manager showed 3.5GB
of physical memory you would be okay, as 0.5GB would be available
for the OS. If Task Manager only showed 3.1GB as available, XP
would only have 100MB, which could lead to a lot of OS paging, or
a system crash. That's why MS recommends a /userva in the range
of 2800 - 2900 MB. The /userva switch gives some memory back to
to OS that is taken by the /3GB switch.

It doesn't have anything to do with RAM as such and what you say above
is not the way it works at all. The 4GT RAM tuning switch changes the
way the "Virtual Address Space" is alloted, regardless of how much RAM
is installed in the computer the 32-bit operating system always has a
full 4GB of Virtual Address Space to work with.

John

 

[Thee Chicago Wolf]

The purpose of the /userva switch is to provide sufficient memory

address space for the XP kernel if the /3GB switch is used. The /3GB
switch adds 1GB to the default 2GB of application memory address
space at the expense of the OS kernel. If Task Manager showed 3.5GB
of physical memory you would be okay, as 0.5GB would be available
for the OS. If Task Manager only showed 3.1GB as available, XP
would only have 100MB, which could lead to a lot of OS paging, or
a system crash. That's why MS recommends a /userva in the range
of 2800 - 2900 MB. The /userva switch gives some memory back to
to OS that is taken by the /3GB switch.

In addition, the extra 1GB provided by the /3GB switch can only
be used by applications that are large address aware, such as
Adobe Photoshop, or Photoshop Elements.

Right, that's if you're using it primarily on a Server, not on XP. XP
isn't going to fall over from starved kernel pages so using USERVA is
moot unless the OP runs out of page table entries. /3GB will take 1GB
from kernel address paging and allocate it to physical and paged
memory. Tech references from MS folks and docs seem to state this.

- Thee Chicago Wolf

 

[John John (MVP)]

Right, that's if you're using it primarily on a Server, not on XP. XP
isn't going to fall over from starved kernel pages so using USERVA is
moot unless the OP runs out of page table entries. /3GB will take 1GB
from kernel address paging and allocate it to physical and paged
memory. Tech references from MS folks and docs seem to state this.

The /3GB switch does not allocate anything to physical and paged memory,
it simply changes the way the Virtual Address Space is devided.

John

 

[Ken Blake, MVP]

Thanks

I will be glad if I can get the machine to show 3.5GB of RAM. Is there any
other way than editing the Boot.ini ??

No, it's mostly dependent on what hardware you happen to have.

 

[Stephen Harris]

Thanks,

How about if you have Qautro Process on windwos XP SP2 ?? will that work ?

I wrote a long post on this topic,
http://groups.google.com/group/microsoft.public.windowsxp.general/msg/4b314125a4ac50c1

I'm not sure the /PAE switch actually has functionality.
Quoting the most relevant part of that post,

SH: Nonetheless, there is hope if you have *Windows XP Pro* 32-bit.

http://www.microsoft.com/whdc/system/platform/server/PAE/PAEmem.mspx

"Operating systems based on Microsoft Windows NT technologies have
always provided applications with a flat 32-bit virtual address space
that describes 4 gigabytes (GB) of virtual memory. The address space is
usually split so that 2 GB of address space is directly accessible to
the application and the other 2 GB is only accessible to the Windows
executive software.

The 32-bit versions of the Windows 2000 Advanced Server and Windows NT
Server 4.0, Enterprise Edition, operating systems were the first
versions of Windows to provide applications with a 3-GB flat virtual
address space, with the kernel and executive components using only 1 GB.
In response to customer requests, Microsoft has expanded the
availability of this support to the 32-bit version of Windows XP
Professional and all 32-bit versions of Windows Server 2003. ...

The virtual address space of processes and applications is still limited
to 2 GB unless the /3GB switch is used in the Boot.ini file. When the
physical RAM in the system exceeds 16 GB and the /3GB switch is used,
the operating system will ignore the additional RAM until the /3GB
switch is removed. This is because of the increased size of the kernel
required to support more Page Table Entries. The assumption is made that
the administrator would rather not lose the /3GB functionality silently
and automatically; therefore, this requires the administrator to
explicitly change this setting.

The /3GB switch allocates 3 GB of virtual address space to an
application that uses IMAGE_FILE_LARGE_ADDRESS_AWARE in the process
header. This switch allows applications to address 1 GB of additional
virtual address space above 2 GB.

The virtual address space of processes and applications is still limited
to 2 GB, unless the /3GB switch is used in the Boot.ini file. The
following example shows how to add the /3GB parameter in the Boot.ini
file to enable application memory tuning:

[boot loader]
timeout=30
default=multi(0)disk(0)rdisk(0)partition(2)\WINNT
[operating systems]
multi(0)disk(0)rdisk(0)partition(2)\WINNT="????" /3GB

SH: I think shifting the extra 1GB of memory to applications
will in some situations result in fewer disk writes and
retrieval from data stored on the disk which is more efficient.

 

[Plato]

I will be glad if I can get the machine to show 3.5GB of RAM. Is there any
other way than editing the Boot.ini ??

wont help