The folks over at Ace's Hardware have taken an Athlon FX-51 and given it a "little" help in cooling from nVENTIV's Mach II Promethia unit. And by a little I mean - 39°C under full load. The Mach II gives 200W of thermal dissipation which has given the Pentium 4 clock speeds well past 4ghz!

Pretty interesting that even though it was strictly a multiplier overclock, meaning the Front Side Bus was left at stock and only the core speed was raised, it leaves the competition in the dust. This type of cooling solution can give you quite an edge on the normal stock speeds you find on the market today. The Mach II cooling system can be yours for about a grand.