Windows 64 Bit Compatibility Question

Hi

I am currently using Windows XP SP 2 32bit, I am thinking of installing the
64 bit version because of the 3.5GB RAM limitation.

The questions I have is about software:

1) I use Office 2007 will this still work?
2) I use Visual Studio Tools for Office 2005, will this work?
3) I use Virtual PC 2007, can i run 32 bit applications inside of this on a
64 bit system?

Regards

D

Sebastian
Fri Mar 21 04:57:34 PDT 2008

DMc2007 wrote:


> I am currently using Windows XP SP 2 32bit, I am thinking of installing the
> 64 bit version because of the 3.5GB RAM limitation.


You're not thinking, since then you would have recognized that there's no
such limitation if you simply use PAE. The only limit is the 2/3 GB user
mode address space per process, and maybe some duble buffering for drivers
which are not PAE aware.

> The questions I have is about software:
>
> 1) I use Office 2007 will this still work?


Counter question: What does "work" mean in terms of Office 2007?

Short to say, it will still launch as before and behave as before. Which is
insufficient for any sane scenario or reliable usage.

> 2) I use Visual Studio Tools for Office 2005, will this work?


Same as above.

> 3) I use Virtual PC 2007, can i run 32 bit applications inside of this on a
> 64 bit system?


Yes.

Theo
Fri Mar 21 05:07:02 PDT 2008

Windows XP SP2 and later by default on NX capable processors
enables PAE in order to enable NX, but limits physical
address space to 32 bits for driver compatibility reasons.


Sebastian G. wrote:
> DMc2007 wrote:
>
>
>> I am currently using Windows XP SP 2 32bit, I am thinking of
>> installing the
>> 64 bit version because of the 3.5GB RAM limitation.
>
>
> You're not thinking, since then you would have recognized that there's
> no such limitation if you simply use PAE. The only limit is the 2/3 GB
> user mode address space per process, and maybe some duble buffering for
> drivers which are not PAE aware.
>
>> The questions I have is about software:
>>
>> 1) I use Office 2007 will this still work?
>
>
> Counter question: What does "work" mean in terms of Office 2007?
>
> Short to say, it will still launch as before and behave as before. Which
> is insufficient for any sane scenario or reliable usage.
>
>> 2) I use Visual Studio Tools for Office 2005, will this work?
>
>
> Same as above.
>
>> 3) I use Virtual PC 2007, can i run 32 bit applications inside of this
>> on a
>> 64 bit system?
>
>
> Yes.

Theo
Fri Mar 21 05:11:12 PDT 2008

You need to re-read the information relative to PAE and
Windows XP. Regardless of PAE, Windows XP is still limited
to 4GB.


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

Windows and PAE
Windows Version Support
Windows 2000 Professional
Windows XP
AWE API and 4 GB of physical RAM

Windows XP SP2 and later
AWE API and 4 GB of physical address space

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



Sebastian G. wrote:
> DMc2007 wrote:
>
>
>> I am currently using Windows XP SP 2 32bit, I am thinking of
>> installing the
>> 64 bit version because of the 3.5GB RAM limitation.
>
>
> You're not thinking, since then you would have recognized that there's
> no such limitation if you simply use PAE. The only limit is the 2/3 GB
> user mode address space per process, and maybe some duble buffering for
> drivers which are not PAE aware.
>
>> The questions I have is about software:
>>
>> 1) I use Office 2007 will this still work?
>
>
> Counter question: What does "work" mean in terms of Office 2007?
>
> Short to say, it will still launch as before and behave as before. Which
> is insufficient for any sane scenario or reliable usage.
>
>> 2) I use Visual Studio Tools for Office 2005, will this work?
>
>
> Same as above.
>
>> 3) I use Virtual PC 2007, can i run 32 bit applications inside of this
>> on a
>> 64 bit system?
>
>
> Yes.

Colin
Fri Mar 21 07:35:35 PDT 2008

1. Yes
2. Yes
3. Yes, once you install an operating system inside a guest you can run the
apps on that.

"DMc2007" <davidmcnaughton_1999@hotmail.com> wrote in message
news:eBqqjO0iIHA.2304@TK2MSFTNGP05.phx.gbl...
> Hi
>
> I am currently using Windows XP SP 2 32bit, I am thinking of installing
> the
> 64 bit version because of the 3.5GB RAM limitation.
>
> The questions I have is about software:
>
> 1) I use Office 2007 will this still work?
> 2) I use Visual Studio Tools for Office 2005, will this work?
> 3) I use Virtual PC 2007, can i run 32 bit applications inside of this on
> a
> 64 bit system?
>
> Regards
>
> D
>
>
>

Charlie
Fri Mar 21 09:09:39 PDT 2008

Colin is correct. I'd only add that you should ensure you have drivers for
your hardware before making the move.

--
Charlie.
http://msmvps.com/xperts64
http://mvp.support.microsoft.com/profile/charlie.russel


"DMc2007" <davidmcnaughton_1999@hotmail.com> wrote in message
news:eBqqjO0iIHA.2304@TK2MSFTNGP05.phx.gbl...
> Hi
>
> I am currently using Windows XP SP 2 32bit, I am thinking of installing
> the
> 64 bit version because of the 3.5GB RAM limitation.
>
> The questions I have is about software:
>
> 1) I use Office 2007 will this still work?
> 2) I use Visual Studio Tools for Office 2005, will this work?
> 3) I use Virtual PC 2007, can i run 32 bit applications inside of this on
> a
> 64 bit system?
>
> Regards
>
> D
>
>
>

Sebastian
Fri Mar 21 11:47:36 PDT 2008

Theo wrote:

> Windows XP SP2 and later by default on NX capable processors
> enables PAE in order to enable NX, but limits physical
> address space to 32 bits for driver compatibility reasons.


That's why you have to enable it explicitly via the /PAE switch.

John
Fri Mar 21 12:03:28 PDT 2008

Sebastian G. wrote:

> Theo wrote:
>
>> Windows XP SP2 and later by default on NX capable processors enables
>> PAE in order to enable NX, but limits physical address space to 32
>> bits for driver compatibility reasons.
>
>
>
> That's why you have to enable it explicitly via the /PAE switch.

Enabling the /PAE on Windows XP will still not provide for memory
addressing above the 4GB boundary.

John

Theo
Fri Mar 21 12:16:58 PDT 2008

Sebastian G. wrote:
> Theo wrote:
>
>> Windows XP SP2 and later by default on NX capable processors enables
>> PAE in order to enable NX, but limits physical address space to 32
>> bits for driver compatibility reasons.
>
>
> That's why you have to enable it explicitly via the /PAE switch.

"but limits physical address space to 32 bits (4GB) for
driver compatibility reasons."

Sebastian
Fri Mar 21 12:54:56 PDT 2008

John John wrote:

> Sebastian G. wrote:
>
>> Theo wrote:
>>
>>> Windows XP SP2 and later by default on NX capable processors enables
>>> PAE in order to enable NX, but limits physical address space to 32
>>> bits for driver compatibility reasons.
>>
>>
>> That's why you have to enable it explicitly via the /PAE switch.
>
> Enabling the /PAE on Windows XP will still not provide for memory
> addressing above the 4GB boundary.


Actually I just didn't catch the meaning to notice that the above is wrong:
NX without PAE switch limits the *virtual address space* to 32 bits, which
is 4 GB minus PCI address range, 1 MB lower memory, config ROMs etc.

With the PAE switch the virtual address space is extended to 36 bits, but
the physical address range is limited to 32 bits. That is, you can actually
fully use the entire 4 GB, since the memory burned by the reserved areas is
remapped to addresses above the 4 GB virtual address limit.

Sebastian
Fri Mar 21 12:57:19 PDT 2008

Theo wrote:

> Sebastian G. wrote:
>> Theo wrote:
>>
>>> Windows XP SP2 and later by default on NX capable processors enables
>>> PAE in order to enable NX, but limits physical address space to 32
>>> bits for driver compatibility reasons.
>>
>> That's why you have to enable it explicitly via the /PAE switch.
>
> "but limits physical address space to 32 bits (4GB) for
> driver compatibility reasons."

Yes, it's wrong and I didn't catch it. NX without PAE limits the *virtual*
address space.

John
Fri Mar 21 13:15:45 PDT 2008

Sebastian G. wrote:

> John John wrote:
>
>> Sebastian G. wrote:
>>
>>> Theo wrote:
>>>
>>>> Windows XP SP2 and later by default on NX capable processors enables
>>>> PAE in order to enable NX, but limits physical address space to 32
>>>> bits for driver compatibility reasons.
>>>
>>>
>>>
>>> That's why you have to enable it explicitly via the /PAE switch.
>>
>>
>> Enabling the /PAE on Windows XP will still not provide for memory
>> addressing above the 4GB boundary.
>
>
>
> Actually I just didn't catch the meaning to notice that the above is
> wrong: NX without PAE switch limits the *virtual address space* to 32
> bits, which is 4 GB minus PCI address range, 1 MB lower memory, config
> ROMs etc.
>
> With the PAE switch the virtual address space is extended to 36 bits,
> but the physical address range is limited to 32 bits. That is, you can
> actually fully use the entire 4 GB, since the memory burned by the
> reserved areas is remapped to addresses above the 4 GB virtual address
> limit.

Don't confuse Virtual Address Space with Physical RAM. With Windows XP
32-bit enabling PAE does not permit the operating system to access RAM
addresses remapped above the 4GB boundary. If the OP has 4GB of RAM in
his machine he will not be able to use all of it. The Physical Address
Space on Windows XP 32-bit is limited to 4GB and using Physical Address
Extensions does not change that limit.

John

Sebastian
Fri Mar 21 14:12:08 PDT 2008

John John wrote:


> Don't confuse Virtual Address Space with Physical RAM. With Windows XP
> 32-bit enabling PAE does not permit the operating system to access RAM
> addresses remapped above the 4GB boundary. If the OP has 4GB of RAM in
> his machine he will not be able to use all of it. The Physical Address
> Space on Windows XP 32-bit is limited to 4GB and using Physical Address
> Extensions does not change that limit.

Argh, now I got it wrong as well. But I found the conclusion: With the /PAE
switch, the kernel does not limit the physical address range at all.

See <http://blogs.msdn.com/carmencr/archive/2004/08/06/210093.aspx>

John
Fri Mar 21 14:36:07 PDT 2008

Sebastian G. wrote:

> John John wrote:
>
>
>> Don't confuse Virtual Address Space with Physical RAM. With Windows
>> XP 32-bit enabling PAE does not permit the operating system to access
>> RAM addresses remapped above the 4GB boundary. If the OP has 4GB of
>> RAM in his machine he will not be able to use all of it. The Physical
>> Address Space on Windows XP 32-bit is limited to 4GB and using
>> Physical Address Extensions does not change that limit.
>
>
> Argh, now I got it wrong as well. But I found the conclusion: With the
> /PAE switch, the kernel does not limit the physical address range at all.

No, with Windows XP the use of the /PAE switch does not change the
available physical address space, it will still be limited to 4GB, the
XP PAE kernel will not make use of RAM addresses remapped above the 4GB
boundary, it is completely limited to the lower 4GB arena. The use of
the /PAE switch is different for 32-bit Server products than it is for
Workstation products.

John

Sebastian
Fri Mar 21 15:06:31 PDT 2008

John John wrote:


>>> Don't confuse Virtual Address Space with Physical RAM. With Windows
>>> XP 32-bit enabling PAE does not permit the operating system to access
>>> RAM addresses remapped above the 4GB boundary. If the OP has 4GB of
>>> RAM in his machine he will not be able to use all of it. The Physical
>>> Address Space on Windows XP 32-bit is limited to 4GB and using
>>> Physical Address Extensions does not change that limit.
>>
>> Argh, now I got it wrong as well. But I found the conclusion: With the
>> /PAE switch, the kernel does not limit the physical address range at all.
>
> No, with Windows XP the use of the /PAE switch does not change the
> available physical address space,


Which is 36 bits, as long as the board is properly wired.

> it will still be limited to 4GB, the

> XP PAE kernel will not make use of RAM addresses remapped above the 4GB
> boundary, it is completely limited to the lower 4GB arena.


As you may read up in the link I provided, the Technet documentation is
obviously not precise enough. When using PAE implied through the NoExecute,
these limits are applied - if you use PAE explicitly, this doesn't happen.

> The use of the /PAE switch is different for 32-bit Server products than

> it is for Workstation products.

This changed in XP SP2.

John
Fri Mar 21 18:49:51 PDT 2008

Sebastian G. wrote:

> John John wrote:
>
>
>>>> Don't confuse Virtual Address Space with Physical RAM. With Windows
>>>> XP 32-bit enabling PAE does not permit the operating system to
>>>> access RAM addresses remapped above the 4GB boundary. If the OP has
>>>> 4GB of RAM in his machine he will not be able to use all of it. The
>>>> Physical Address Space on Windows XP 32-bit is limited to 4GB and
>>>> using Physical Address Extensions does not change that limit.
>>>
>>>
>>> Argh, now I got it wrong as well. But I found the conclusion: With
>>> the /PAE switch, the kernel does not limit the physical address range
>>> at all.
>>
>>
>> No, with Windows XP the use of the /PAE switch does not change the
>> available physical address space,
>
>
>
> Which is 36 bits, as long as the board is properly wired.
>
> > it will still be limited to 4GB, the
>
>> XP PAE kernel will not make use of RAM addresses remapped above the
>> 4GB boundary, it is completely limited to the lower 4GB arena.
>
>
>
> As you may read up in the link I provided, the Technet documentation is
> obviously not precise enough. When using PAE implied through the
> NoExecute, these limits are applied - if you use PAE explicitly, this
> doesn't happen.
>
>> The use of the /PAE switch is different for 32-bit Server products than
>
>
> > it is for Workstation products.
>
> This changed in XP SP2.

No, it hasn't. Regardless of which switch is used or not used in the
boot.ini file Windows XP computers with 4GB of RAM installed cannot see
or use all of the installed RAM if one of the Service Packs is
installed. The information on the memory addressing and the use of /PAE
in the article that you point to applies to servers only, it does not
apply to Windows XP.

Physical Address Extension - PAE Memory and Windows
http://www.microsoft.com/whdc/system/platform/server/PAE/PAEdrv.mspx

How PAE X86 Works
http://technet2.microsoft.com/windowsserver/en/library/26eccf33-2454-4222-841a-c6d5aa1fc54c1033.mspx?mfr=true

The system memory that is reported in the System Information dialog box
in Windows Vista is less than you expect if 4 GB of RAM is installed

Who ate my memory?
http://blogs.msdn.com/dcook/archive/2007/03/25/who-ate-my-memory.aspx

The RAM reported by the System Properties dialog box and the System
Information tool is less than you expect in Windows Vista or in Windows
XP Service Pack 2
http://support.microsoft.com/kb/888137

John