Windows XP Pro 64 bit not detecting my 4GB of Ram?

dazftw

Right so, After about 2 days of trying to fix vista with 4GB of ram I gave up it just wouldnt work. So I got myself a copy of Windows XP pro 64bit edition and installed that but it crash on installing, so I took out the 2 gigs of the memory and reinstalled worked fine. So setup all my drivers and what not, shutdown the pc installed the other 2 gigs back in booted up fine and theres me thinking ive got 4 gigs of ram now


My computer tells me its only 2GB? In CPU-Z its telling me 4GB!? I dunno which to believe!

Any ideas? If you need any more info just ask

Ram is OCZ PC-8500

Mobo is Asus P5N32-E SLI

Capt'n Midnight

start at the beginning.

what does it say in c:\boot.ini ?

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

dazftw

Oh, that page doesn't work

Oh yea I tried the msconfig way, it wont let me go past 2048 I can change the value but it wont stay that way!

Heres what it says anyway hope it helps:

[boot loader]
timeout=30
deafault=(0)disk(0)rdisk(0)partition(1)WINDOWS
[operating systems]
deafault=(0)disk(0)rdisk(0)partition(1)WINDOWS="Windows XP Professional x64 Edition" /noexcute=optin/fastdetect/maxmem=2048

maxmem im guessing = 2GB

Ginger

Maxmem is the switch that is doing it for you.. you can delete it (but take a copy of the ini first!!!!)

See http://support.microsoft.com/kb/833721

dazftw

How do I back it up?

Is this what your talking about

/maxmem=number
This switch specifies the amount of RAM, in bytes, that Windows can use. For example, if you want Windows to use less than 64 MB of memory, use the /maxmem=64 switch.

However, the /maxmem switch does not account for memory holes. Therefore, we recommend that you use the /burnmemory switch instead. The /burnmemory switch accounts for memory holes.

For example, if you use the /Maxmem=64 switch, and the system requires 64 MB of memory to load, there may not actually be 64 MB availalbe to the system because of a memory hole. In this scenario, Windows would not start.

For more information, click the following article number to view the article in the Microsoft Knowledge Base:
108393 (http://support.microsoft.com/kb/108393/) MAXMEM option in Windows NT Boot.ini file

Is there a Memory Remap feature in your BIOS? If so, disable it. I've seen this on the Asus P5B, when using 4GB RAM it does the following:

Disabled: The BIOS and Windows (32-bit) both show 3008MB
Enabled: The BIOS reports 4096MB but Windows only reports 2GB

dazftw

Karsini wrote:

Is there a Memory Remap feature in your BIOS? If so, disable it. I've seen this on the Asus P5B, when using 4GB RAM it does the following:

Disabled: The BIOS and Windows (32-bit) both show 3008MB
Enabled: The BIOS reports 4096MB but Windows only reports 2GB

I dont think there is, but ill go look now.. Pretty sure theres not... I checked it before!

dazftw

That didnt work, but what I did was when I ran msconfig under the general tab I checked the normal startup box and restared and there you go.. 4096mb up and running

Thanks for all the help lads

Ginger

To back it up just copy the boot.ini file..

When you delete the /MAXMEM switch it uses the full amount of RAM supported by the OS rather than limiting you to the amount of memory that you specify in the ini file. Hence when you dont use the switch in XP 32Bit you still see 2048MB RAM

If you use the same switch you still see the same amount :P Glad its working out..