Virtual Memory in Windows XP

26 07 2008
Version 1.6 — Last Updated February 21, 2006

by Alex Nichol
(MS-MVP – Windows Storage Management/File Systems)
© 2002-2005 by Author, All Rights Reserved


This page attempts to be a stand-alone description for general users of the way Virtual Memory operates in Windows XP. Other pages on this site are written mainly for Windows 98/ME (see Windows 98 & Win ME Memory Management) and, while a lot is in common, there are significant differences in Windows XP.

What is Virtual Memory?

A program instruction on an Intel 386 or later CPU can address up to 4GB of memory, using its full 32 bits. This is normally far more than the RAM of the machine. (The 32nd exponent of 2 is exactly 4,294,967,296, or 4 GB. 32 binary digits allow the representation of 4,294,967,296 numbers — counting 0.) So the hardware provides for programs to operate in terms of as much as they wish of this full 4GB space as Virtual Memory, those parts of the program and data which are currently active being loaded into Physical Random Access Memory (RAM). The processor itself then translates (‘maps’) the virtual addresses from an instruction into the correct physical equivalents, doing this on the fly as the instruction is executed. The processor manages the mapping in terms of pages of 4 Kilobytes each – a size that has implications for managing virtual memory by the system.

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Optimize Windows XP Virtual Memory

26 07 2008

Page file or virtual memory plays a vital part in determining our system performance. At least 5 years new operating system will come out with larger memory requirement. A good example is Microsoft Windows Vista operating system . It needs at least 512mb ram to run properly without the cool 3D effects.

Unfortunately, RAM prices did not decrease as fast as RAM requirement had increased. This meant that Windows users had to either fork out a fortune for more RAM or run only simple programs. Neither were attractive options. An alternative method was needed to alleviate this problem.

The solution is the operating systems nowadays came up with was to use some space on the hard disk as extra RAM. Although the hard disk is much slower than RAM, it is also much cheaper and users always have a lot more hard disk space than RAM. So, Windows was designed to create this pseudo-RAM or in Microsoft’s terms – Virtual Memory, to make up for the shortfall in RAM when running memory-intensive program.

Now, in this guide, I will tell you how to optimize your page files or virtual memory. It’s very easy and you might wanted to do this to avoid performance-related problem such as the blue screen of death.

Right click on My Computer icon and click “Properties”.

Go to the “Advanced” tab.

Choose Performance and click “settings”.

Go to the “Advanced tab”

Change the setting for virtual memory

The best setting is the virtual memory size should be 1.5 times of your memory size (according to the Microsoft knowledge base)

Set the initial size and the maximum size equally the same. (Both are 1.5 times the amount of your system memory.

Choose the partition with less file access if can. Setting the page files on another drive other than a drive which has Windows files is much recommended.