For all of you out there that are following the progress of the 3Gb switch, I have found another piece of the puzzle that has "puzzled" me for quite some time.
I know that you can look at the boot.ini file or the load area of XP to see what boot options should have been loaded, or to rephrase that, how was the machine probably booted? But, that only goes as far as determining what the default is, not whether or not someone chose another boot profile. But I have just run across the location in the registry that tells you for sure how the machine booted. If you want to check, go to HKLM\System\CurrentControlSet\Control. Make sure you click on the Control key, not its plus sign. Under it you will find the value name SystemStartOptions, and the value for it is what boot options were used for the current boot session. Bingo! On my machine at this time I find that value to be "FASTDETECT 3GB USERVA=2900 SOS NOEXECUTE=OPTIN".
If some of this looks confusing or foreign, please ask for help before you venture out into the registry - a wrong move there could cause you major grief. You should also search the newsgroup comp.cad.solidworks for discussions on the 3Gb switch as you will learn a whole lot about what, why, and how.
My thanks to Microsoft for this new piece of information.