I said for one week ago some simillary...Again.
AM3 socket=941 pins, standartly 938 electrically active into motherboards AM3 CPUs=938pins
AM3+ socket=942 pins AM3+ CPUs=940 or 941 pins
my theory: some ASUS boards has from begining at AM3 boards (from support list) electrically active all possible conections for pins, so this is 941. Second condition is big flash rom