4GB Memory

  • Thread starter Thread starter Clayton
  • Start date Start date
No - the memory above about 3.25Gb is used for hardware devices and other
stuff and is not available/shown to you. Be assured the 4GB is all there and
in use.

Do a Google search on boot.ini and you'll be provided with possible switches
to use. One is /PAE which could help.
 
Cheers


Jerry said:
No - the memory above about 3.25Gb is used for hardware devices and other
stuff and is not available/shown to you. Be assured the 4GB is all there
and in use.

Do a Google search on boot.ini and you'll be provided with possible
switches to use. One is /PAE which could help.
Click to expand...
 
Windows is reading 3.25GB how can I get it to read 4GB? I have searched
Google and ran the /PAE in the boot.ini but it's still reading as 3.25GB
Can some please tell me what I need to put in the boot.ini for it to read
4GB

cheers
 
Clayton said:
Windows is reading 3.25GB how can I get it to read 4GB? I have searched
Google and ran the /PAE in the boot.ini but it's still reading as 3.25GB
Can some please tell me what I need to put in the boot.ini for it to
read 4GB

cheers
Click to expand...

I suspect the rules are different for SP1 versus SP2. SP2 includes
DEP (Data Execution Protection), and NoExecute and PAE are tied together
for SP2. So SP2 changed some things.

http://www.ocforums.com/showthread.php?p=4705537

The bottom post on that page shows a boot.ini, but to me it looks like
a boot.ini suitable for WinXP SP1. For SP2, you might need something
like /noexecute=AlwaysOff /PAE in the boot.ini .

This shows a list of the boot.ini options, but does not explain all
the consequences of using them.

http://web.archive.org/web/20070224...technet/sysinternals/information/bootini.mspx

I really think you should be happy at the 3.25GB level. Yes, you've lost
0.75GB of memory, but DEP is working for you, so some buffer overflow
exploits will be stopped.

http://en.wikipedia.org/wiki/Data_Execution_Prevention

You'll notice in the ocforums thread (first link), the guy doing the
experiments kinda gave up. He had two drivers failing with some of that
stuff enabled. If doing these kinds of experiments, make sure you are
prepared for the worst (i.e. use a throwaway boot HDD). You don't want
to do this to a working system with valuable data on it.

SP2 caused less RAM to be reported, in exchange for enabling DEP and
making the OS slightly more secure. The article here gives examples.

http://support.microsoft.com/kb/888137/en-us

By including "noexecute alwaysoff pae 4GB" in your search terms,
you may find more experiments by the dedicated few.

Paul
 
Clayton said:
Windows is reading 3.25GB how can I get it to read 4GB? I have searched
Google and ran the /PAE in the boot.ini but it's still reading as 3.25GB
Can some please tell me what I need to put in the boot.ini for it to
read 4GB

cheers
Click to expand...

Didn't you understand Jerry's answer? To repeat, you can't.
 
Install a 64 bit operating system. THAT is the only way. 32 bit systems
can only see 4 GB address space AND hardware addressing MUST be in that
space. SO you have what remains AFTER the hardware addresses used up.
What you see is what is available. And it will NEVER read 4 GB with 32 bit.
 
Clayton said:
Windows is reading 3.25GB how can I get it to read 4GB? I have searched
Google and ran the /PAE in the boot.ini but it's still reading as 3.25GB
Can some please tell me what I need to put in the boot.ini for it to read
4GB

cheers
Click to expand...
If you just want XP to show you that you do have 4 GB, hit Start>Run
and type msinfo32. It'll take 2-3 seconds to to gather the info. When
the info displays look down the list and you will see, "Total Physical
Memory 4096.00 MB". XP gets to use what's left after all the
harware address ranges are reserved.

ID
 
Bob said:
Didn't you understand Jerry's answer? To repeat, you can't.
Click to expand...

I think he did. Jerry began to talk about PAE. PAE allows the CPU to
address more than 4 GB. But unfortunately, desktop editions of Windows
won't go that high
 
Hi Clayton,

This article may explain it:

4 GB RAM in Windows XP
http://members.cox.net/slatteryt/RAM.html

--
HTH,
Curt

Windows Support Center
www.aumha.org
Practically Nerded,...
http://dundats.mvps.org/Index.htm

| Windows is reading 3.25GB how can I get it to read 4GB? I have searched
| Google and ran the /PAE in the boot.ini but it's still reading as 3.25GB
| Can some please tell me what I need to put in the boot.ini for it to read
| 4GB
|
| cheers
|
|
|
| | > Cheers
| >
| >
| > | >> No - the memory above about 3.25Gb is used for hardware devices and
other
| >> stuff and is not available/shown to you. Be assured the 4GB is all
there
| >> and in use.
| >>
| >> Do a Google search on boot.ini and you'll be provided with possible
| >> switches to use. One is /PAE which could help.
| >>
| >> | >>> Is there a way I can get XP to show 4GB memory without using 64-bit?
| >>>
| >>>
| >>
| >>
| >
|
 
Would there be any performance gains if I was to use 4X 1GB modules instead
of 2X 2GB modules?
 
Maybe, if the motherboard supported interleaving, BUT that would be
subject to benchmark testing.
 
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