AMD Deneb AM3 chips will work in AM2+ socket
 

AMD managed to pull one small miracle. The first 45nm native quad-core from AMD labs, codenamed Deneb and Deneb FX, will be native socket AM3. However, AM3 will have an identical pin out as socket AM2+ (Socket 940) and if you plug Deneb in Socket AM2 it will work as a DDR2 chip, and if you plug it in socket AM3 it will work as DDR3. This will be very convenient, as it will make transition easier.

http://www.fudzilla.com/index.php?op...236&Ite mid=1