Since 2006.May.23 when AMD released the Athlon 64 ("Orleans"), the Athlon 64 X2 ("Windsor") and the Athlon 64 FX ("Windsor") as the first AMD processors to support this technology, every newer CPU supports it.
As for intel, the first ones were Pentium 4 662 and 672, Pentium Extreme Edition 955 and 965 followed by Pentium D 920 and 960.
-------------------------
World's best Red Alert 2: Yuri's Revenge mod and Star Trek: Starfleet Command 3 mod: Overmind.ro