The link below has the entire article, but here is a quote from the Microsoft Knowledge Base>
When you set up a 32-bit version or a 64-bit version of Windows Server 2003 or Windows XP, a page file is created that is one and a half times the amount of RAM that is installed in the computer provided there is sufficient free space on the system hard disk. However, as more RAM is added to a computer, the need for a page file decreases. If you have enough RAM installed in your computer, you may not require a page file at all, unless one is required by a specific application.
The article is at this link: http://support.microsoft.com/kb/889654/en-us
Note that there is an exception for applications that may require additional page file access.