32-bit / 64-bit memory


M

Matthew Dill

Ok, so we all know about 32-bit vista being unable to realize 4gb of memory.
Currently, because my video card has 768mb of memory, my 4 gigs of system
memory is only displaying as about 3gb (as expected).

I have two questions:
1) Are there any registry hacks to open up extra available memory
mapping space
2) Does windows offer a trade-up program? I mean comon, I purchased
vista upgrade for 32-bit, but now need 64-bit. I have a 64-bit version of
windows XP just sitting around that I could easily upgrade to Vista-64.
Anyone know of a Vista "swap" program?
 
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G

Guest

Hello Matthew,

Microsoft Knowledge Base article 932795
(http://support.microsoft.com/kb/932795) outlines the various options
available for upgrading and installing Windows Vista 64-bit editions.

To order Windows Vista 64-bit media for a small fee (depending on your
location), please visit
http://www.microsoft.com/windows/products/windowsvista/editions/64bit.mspx.
At the bottom of the page, select the language that you prefer and click on
the Go button, then follow the on-screen instructions. You will need to have
your Windows Vista product key ready in order to verify your Windows license.

Before migrating to 64-bit, ensure that all of your devices and peripherals
have 64-bit drivers available, and check with the manufacturers of any
applications you may use to verify compatibility with 64-bit Windows.

--
Regards,
Kristan M. Kenney
Microsoft MVP [Windows - Shell/User]

This posting is provided "AS IS" with no warranties, and confers no rights.
 
R

Richard G. Harper

1. No. This is an OS limitation, and cannot be bypassed.

2. Your upgrade rights depend on where you got your copy of Windows. If
your version of Vista didn't come with both discs AND is a retail version,
you can order the 64-bit disc for a nominal charge. If your copy of Vista
is an OEM copy your "upgrade" rights to get a 64-bit version are determined
by the OEM who sold you the CD. You may or may not be able to get the
64-bit disc.

--
Richard G. Harper [MVP Shell/User] (e-mail address removed)
* NEW! Catch my blog ... http://msmvps.com/blogs/rgharper/
* PLEASE post all messages and replies in the newsgroups
* The Website - http://rgharper.mvps.org/
* HELP us help YOU ... http://www.dts-l.org/goodpost.htm
 
T

Tim Slattery

Richard G. Harper said:
1. No. This is an OS limitation, and cannot be bypassed.

I agree, but I think it's a hardware limitation, and the OS can't do
anything about it.
 
Tim Slattery said:
I agree, but I think it's a hardware limitation, and the OS can't do
anything about it.

It can't be a hardware limitation or vista 64 would have the same
limitation.
It is down to how the software uses the hardware, i.e. an OS limitation.
 
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Tim Slattery said:
It's a limitation of 32-bit hardware. You can run 64-bit Vista (or any
other 64-bit OS) only on 64-bit hardware.

Except that isn't what the OP was asking about.
He was asking if there were any hacks to make vista 32 support more RAM.
This is not a hardware issue.
 
dzomlija said:
Actually, it IS a hardware limitation. A 32-Bit Hardware limitation.

32-Bit in Hex translates to FFFFFFFF Bytes. In decimal, this number is
4,294,967,295 bytes.

4,294,967,295 bytes = 4,194,303 KB
4,194,303 KB = 4,096 MB
4,096 MB = 4GB

If your hardware is 32-Bit (i.e. it uses a 32-Bit Address Bus), then
the system must support PAE (Physical Address Extensions) to be able to
support memory spaces larger than 4GB. This is most common in 32-Bit
Server Operating Systems, such as Windows Server 2003

64 Bit Addressing (FFFFFFFFFFFFFFFF bytes in Hex) is
18,446,744,073,709,551,615 Bytes of address space!. To get the
KB/MB/GB/TB values, keep dividing by 1024.

This is not relevant to what the OP was asking.
It is a software limitation that prevents his Vista 32 bit from accessing
more RAM.

BTW just because a processor has 64 bit registers and addressing doesn't
mean it can address 2^64 bytes as they tend not to have enough pins to
actually support that much RAM.
 
T

Tim Slattery

Except that isn't what the OP was asking about.
He was asking if there were any hacks to make vista 32 support more RAM.
This is not a hardware issue.

There's no such software hack because the limitation is a hardware
issue.
 
dzomlija said:
But it is a hardware issue. If 32-Bit hardware cannot support memory
spaces greater than 4GB (2^32 Bytes), then neither can 32-Bit Software.
if Matthew wants to use more than 4GB Memory, then he must either move
to 64-Bit Hardware (which is the norm today) and use a 64-Bit Operating
System, or he must move to a Server OS that supports PAE.

You are not arguing about anything to do with what the OP said.
I know how processors work (I did actually work on a processor at one time,
not a micro but the principles are the same).
While what you say is true it is not relevant at this time.
 
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J

jorgen

Tim said:
There's no such software hack because the limitation is a hardware
issue.

It depends on the hardware. A 32-bit cpu (and OS, in the Windows-family
this applies only to server editions) can address more than 4GB, but to
take advantage of that, the motherboard and chipset must also support
it, some do, others don't.

Some 64-bit boards don't even have support for more than 4GB (the cpu
does, but not the rest of the system).
 
T

Tim Slattery

jorgen said:
It depends on the hardware. A 32-bit cpu (and OS, in the Windows-family
this applies only to server editions) can address more than 4GB, but to
take advantage of that, the motherboard and chipset must also support
it, some do, others don't.

You're talking about PAE (Programmed Address Extensions) which adds
(IIRC) 4 bits to the address space. AFAIK, no versions of 32-bit Vista
handle PAE. Some MS server OSs do.
Some 64-bit boards don't even have support for more than 4GB (the cpu
does, but not the rest of the system).

I'm sure that's true.
 
J

jorgen

Tim said:
You're talking about PAE (Programmed Address Extensions) which adds
(IIRC) 4 bits to the address space. AFAIK, no versions of 32-bit Vista
handle PAE. Some MS server OSs do.

That is true, Vista doesn't go up there. But the point was, the
limitation is not in the hardware (...), but in the software
 
T

Tim Slattery

jorgen said:
That is true, Vista doesn't go up there. But the point was, the
limitation is not in the hardware (...), but in the software

But what percentage of motherboards support PAE? And of those that
have the required chipset, etc; what percentage can actually seat more
than 4GB?
 
J

jorgen

Tim said:
But what percentage of motherboards support PAE? And of those that
have the required chipset, etc; what percentage can actually seat more
than 4GB?

The OP says he has a 64-bit XP laying around, so i guess he has a newer
board with a 64-bit CPU. So there is a really good chance that his
hardware can go above 4G
 
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B

Brian W

Tim Slattery said:
But what percentage of motherboards support PAE? And of those that
have the required chipset, etc; what percentage can actually seat more
than 4GB?
My motherboard (X38 chipset) will support 8GB of RAM (but obviously only see
~3.5GB on a 32-bit system)
 
J

jorgen

Brian said:
My motherboard (X38 chipset) will support 8GB of RAM (but obviously only
see ~3.5GB on a 32-bit system)

If you were to use a 32-bit server windows or linux (in pae mode), and
enabled memory remapping, you would be able to use all 4GB
 
K

Kieran

So if someone bought a copy of vista 32bit OEM and built their own machine,
could they upgrade to 64bit vista of the same version by using the CD key
from the 32bit and the DVD of the 64bit they had sent to them? As a fresh
install is recommended.




Richard G. Harper said:
1. No. This is an OS limitation, and cannot be bypassed.

2. Your upgrade rights depend on where you got your copy of Windows. If
your version of Vista didn't come with both discs AND is a retail version,
you can order the 64-bit disc for a nominal charge. If your copy of Vista
is an OEM copy your "upgrade" rights to get a 64-bit version are determined
by the OEM who sold you the CD. You may or may not be able to get the
64-bit disc.

--
Richard G. Harper [MVP Shell/User] (e-mail address removed)
* NEW! Catch my blog ... http://msmvps.com/blogs/rgharper/
* PLEASE post all messages and replies in the newsgroups
* The Website - http://rgharper.mvps.org/
* HELP us help YOU ... http://www.dts-l.org/goodpost.htm


Matthew Dill said:
Ok, so we all know about 32-bit vista being unable to realize 4gb of
memory. Currently, because my video card has 768mb of memory, my 4 gigs of
system memory is only displaying as about 3gb (as expected).

I have two questions:
1) Are there any registry hacks to open up extra available memory
mapping space
2) Does windows offer a trade-up program? I mean comon, I purchased
vista upgrade for 32-bit, but now need 64-bit. I have a 64-bit version of
windows XP just sitting around that I could easily upgrade to Vista-64.
Anyone know of a Vista "swap" program?
 
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B

Brian W

Kieran said:
So if someone bought a copy of vista 32bit OEM and built their own
machine,
could they upgrade to 64bit vista of the same version by using the CD key
from the 32bit and the DVD of the 64bit they had sent to them? As a fresh
install is recommended.

The keys are interchangeable. I've installed 64-bit version using my 32-bit
key, and I installed a 32-bit version using a key supplied with a 64-bit
disc. Both were generic OEM DVDs.
 

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