32bit processors and operating systems have a limitation of 3GB. Programs are limited to 2GB of RAM. These tweaks increase the OS’s ability to recognize more RAM and increase the ceiling for programs that can recognize more than 2GB of RAM.
Tweaks can be dangerous if you don’t check everything twice!
http://www.microsoft.com/whdc/system/platform/server/PAE/PAEmem.mspx <- Reference
To get more from Windows XP, you have to modify your Boot.ini file. You have to be familiar with windows explorer. (You must show hidden and system files. If the boot.ini file is read only, uncheck it to make changes.
Windows XP
[boot loader]
timeout=30
default=multi(0)disk(0)rdisk(0)partition(1)\WINNT <-yours may be different!
[operating systems]
multi(0)disk(0)rdisk(0)partition(1)\WINNT=”Windows XP Professional” /PAE /3GB <-add this
The /3gb switch allows programs written specifically to use more than 2gb of ram.
Windows Vista
To add to Vista’s boot process, from a cmd line (you must run the cmd line as an administrator)-
type:
BCDEDIT /SET PAE ForceEnable
In Vista, To get programs written for more than 2gb of ram:
BCDEDIT /Set IncreaseUserVa 3072
Note: In Vista, you can type BCDEDIT and hit enter to see the PAE and UserVA settings