The New Socket AM2 With 940 Pins
At first glance, the new socket looks no different.
The new Socket AM2 is connected to the CPU by 940 pins.
The old model, Socket 939, has 939 pins.
Socket AM2 has the same number of pins as the originally envisaged Athlon 64 with Hammer core (Socket 940), but is not compatible. In addition, the new AM2 CPUs don't fit into Socket 940.
The first socket for Athlon 64 and Opteron also has 940 pins.