XP sp2 /3GB switch

A friend has a newer custom built intel 32bit system with XPSP2 installed and 4 GB of DDR memory.

The main program used on this machine is the newest version of Photoshop.

His problem is in trying to use the 3GB switch in the boot.ini file. This switch changes the default windows behavior of always allocating half the memory for the OS. The switch reduces memory used by windows down to 1G while allowing the other 3G to be used by programs. For a little info check this link:

http://searchwinsystems.techtarget.c...tml?bucket=ETA

As described in that link, he's included 2 lines in his boot.ini file so he can boot with or without the switch.

The problem is that when booting with that switch, his machine won't boot. I'm unable to do any tests because I don't have 4G of memory.

Does anyone here have experience with this switch?

Have a look at these MS pages.

http://support.microsoft.com/kb/888732

http://support.microsoft.com/kb/q291988/

http://support.microsoft.com/kb/Q833721

and ...

My interpretation of these, contrary to the article, is that what the switch is doing is allowing 3GB of virtual address space instead of the default of 2GB, and has nothing to do with how Ram is being allocated.

This article indicates that an application can not use the 3GB address space, unless it was specifically programmed to use it.

And, this one indicates you may get disk errors, depending on your graphics adapter.