>>723432249
PAE allows more than 4GB of RAM, you're still limited to 4GB per process, but 32bit w/PAE CPUs did 36bit (64GB) then later 40bit (1TB)
Everything except client versions of WindowsNT and Win9x supported it (win9x couldn't support it)
Windows NT supported it fine, but client versions were limited to 4GB since certain device drivers (CREATIVE LABS, FUCK YOU) would crash the kernel if called to access memory outside 4GB. Windows Server supported it fine and wouldn't install client multimedia drivers to ensure that never happened on a server.
Thank Creative Labs for the 4GB limit on Windows2000/XP.