Unlocking Full RAM on Win XP X86

canivari

canivari

New Member
If you have 4GB of RAM or more and you are running Windows XP 32Bits
there is a trick to adress all the physicall RAM under the Windows
and start running in 36Bits so he can manage all the RAM until 64GB of
physicall RAM installed:

Note: Microsoft blocked the Operating Systems until the 4GB of RAM because there are some drivers that dont load or can create BSODs at the startup because they cant manage very well with the OS operating at 36 Bits.
So if you gonna try this make sure you have back up everything in your computers first.

So, what you need is to enable an Program in XP so he can boot with your physicall RAM (until 64GB) and that program is PAE (Physical Address Extension mode)and to do that just need to :

edit c:\boot.ini with notepad

Change something like:
multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Professional" /NOEXECUTE=OPTIN /FASTDETECT

To:
multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Professional" /NOEXECUTE=OPTIN /FASTDETECT /PAE

Save and reboot. You should now see (and use) the total of your physicall RAM because its now running in a 36-bit mode.
 
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tyttebøvs

New Member
To make a note: The "noexecute" option is dep-related (default). DEP invokes the pae kernel (so you don't even need the switch).

And with pae comes some of the problems you describe, which is why they limited the pae kernel to 4GB.
 
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tyttebøvs

New Member
The other thread is actually about modifying the kernel to remove the limitation. That exe might or might not do it, and might or might not contain unwanted stuff.
 
linkin

linkin

VIP Member
Someone here used it and stated it was clean. that was one of the other threeads though.

If i still had a WinXP machine and 4gb of ram in it i might have tried it, but i have no need now.
 
canivari

canivari

New Member
tyttebøvs said:
That will not work. Microsoft still has a 4GB limitation in the kernel.
Click to expand...

tyttebøvs said:
And to just trust that is very, very, very, very, very, very, very, very ... very, very, very dangerous.
Click to expand...

Motoxrdude said:
Not saying it will work, but xp does not have a ram limitation. It's just the whole 32bit memory addressing problem.
Click to expand...

tyttebøvs said:
But it really is a limitation defined by Microsoft.
Click to expand...

whs said:
What a hoax!!!
Click to expand...

So, gentlemans my question is:

If the X86 OS got an limitation of nearly 4GB of Ram, how can an Windows Server 2003 32bits Datacenter Edition can physicaly manage up to 128GB of RAM with PAE enabled as you can see on MSDN at microsoft under
"Physical Memory Limits: Windows Server 2003"
with short description right above and i quote:
"The following table specifies the limits on physical memory for Windows Server 2003. Limits over 4 GB for 32-bit Windows assume that PAE is enabled."

Link for MSDN from microsoft:
http://msdn.microsoft.com/en-us/library/aa366778(VS.85).aspx

Do you think that microsoft have been lying to theyre clients until now?
If you read carefully that page you can see that is an somewhat licensing
problem in each X86 (32 Bit) version of Windows isnt it?
So, as i said before, the only limit gentlemens is that some drivers that were designed for windows XP just cant load or got corrupted when you enable PAE. Since a few years that Intel (dont know about AMD or other brands) have been making their CPUs allready with 36Bits extensions so that the RAM can go until 128GB of RAM (even if the PAE only manage until 64GB,isnt more than enough??).
The name PAE (Physicall Adress Extension) says everything (Let the entensions (in this case 36Bits)from CPU manage the Physicall RAM because windows it self isnt an 32Bit OS is OS that was produced for 32Bit CPUs but if the CPUs can manage more than 32Bits you only need to unblock the OS so the CPU can manage the rest.

At the moment i am running my system with Window 7 X86 with PAE enabled and physically i got 8GB RAM DDR2 667Mhz Fully Bufered with that patch that i putted here in the forum e few days ago for you and i can tell you that is not a trick.
I ve been using SQL databases, virtualization , hardware testers, loading my RAM until the limits and so far not even 1 error as you can see an printscreen of my desktop from a few days ago here:

http://i777.photobucket.com/albums/yy57/canivari/Untitled.png

So, if you still think that isnt possible, i say it is.
Hell, even Microsoft says its possible...
But with PAE enabled!
 
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canivari

canivari

New Member
tyttebøvs said:
I am saying that altering the boot.ini under xp will give you nothing more than what you already had.
Click to expand...

So, if is not working in your machine,try to force it like this:

At the moment you boot.ini is looking something like this:

multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Professional" /NOEXECUTE=OPTIN /FASTDETECT /PAE

Change iit to:

To:
multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Professional" /NOEXECUTE=OPTIN /FASTDETECT /force PAE


(had the force before PAE and dont forget the space)
Reboot your machine and give it a try.

If it still doesnt boot with all your Physicall RAM you can try the switch that Microsoft uses (BUT YOU NEED TO HAVE MORE THAN 5GB OF RAM TO USE THIS ONE !!) to test all theire 32Bit OSs :

multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Professional" /NOEXECUTE=OPTIN /FASTDETECT /nolowmem
 
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tlarkin

tlarkin

VIP Member
tyttebøvs said:
I am saying that altering the boot.ini under xp will give you nothing more than what you already had.
Click to expand...

I agree, you can make it display that it has 4Gigs of RAM, but in reality it will not utilize it. If I recall, windows 98 could display in system properties that it had more than 512MB of RAM but it could not address more than 512MB of RAM.
 
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tyttebøvs

New Member
Also, if the switch worked, why would you begin to apply a patch to the kernel in your Vista to gain access to memory above 4G?
 
canivari

canivari

New Member
tlarkin said:
I agree, you can make it display that it has 4Gigs of RAM, but in reality it will not utilize it. If I recall, windows 98 could display in system properties that it had more than 512MB of RAM but it could not address more than 512MB of RAM.
Click to expand...

Have you stress all the 4GB of RAM that is showing now and see if it uses or not?
 
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