Just curious as to why a mac pro with 10GB shows only 2GB with XP 32bit. it should show 3-3.5Gb surely? There cannot be that many devices on the BUS using 2GB of address space in a MAC Pro (the only changes from default spec are the 512MN 8800GT (there is half a gig) and a USB card (probably occupying about 256KB at most). In my old PC with a pari of 768MB 8800GTX cards windows XP found 2.25GB out of 4. anyone else seen this ? just curious, not looking for a 'fix' (No I am not gonna use XP64 cos I can't be bothered to mess around with my USB 5.1 headset).