If it were me I would set it somewhere between 512MB and 768MB. Or just let Windwos handle it.

As for me, I would probably set it to 100-150 since that is quite a large amount of RAM.

although the rule of thumb is to have virtual memory 2X that of Physical memory, with 512mb Rd RAM, the page file would hardly be used.
 
Though in any case, put it in one partition, by itself.
give it a dedicated Partition, the first physical Partition on the second hard-disk (Not the Same HD as your installed OS is on). That should give best performance.
 
Cheers,
 
PS: I have allways been curious, does it matter what file system you use for the swapfile-partion? NTFS or FAT32? For performance that is...

I'd go with clutch on its size & with reversing_drive as to its location

Oh, when I stated the size as being 100-150, I meant using a static file size where the min and max are the same, but set to a value of 100 or 150MB. I didn't realize that it could be viewed as a variable size setting until just now.
 
While I run large apps as well (CAD, FEA, and development crap), I have yet to run out of memory using 150 for the pagefile on systems with 256MB RAM, let alone the 512 I have now. I would just rather not have the system think there's a ton of pagefile space to write to, and I don't want to waste the disk space on anything larger.

It will lock the pagefile and not expand it once the size is set. I have seen it NT boxes cap out when running that same CAD/FEA combo at work run out of memory with 128MB RAM and 200MB pagefile (this was during the demo phase of the software, and the workstations now have 384MB RAM and 200MB swap files with no issues).
 
As for the space consideration, I just don't care for throwing away the space. The smallest drive I use is a 25GB in my workstations, but I still don't care to waste space on something that isn't needed (much in the same way you recommend disabling services that you feel aren't necessary, to keep from throwing RAM away).

I think Memory*0,75 and or atmnost 1 is quite enought if the memory is ranging up to 512 Mb.
 
I'm running W2K Advanced Server with 1000MHz Pc 166 Memory. And I have totally disabled pasging file. Inspite a very huge presure by Various applications I haven't notice OS to swap.