Which one is better core 2 duo or core 2 quad or core 2 extreme

[Imtisal zaib]

which one is better core 2 duo or core 2 quad or core 2 extreme?

 

[AlexHYS]

Core 2 Extreme,but it is very obsolete and I suggest a i5 or i7.They will blow the Core 2 Extreme out of the water.

 

[Scott_D_Bowen]

They're all bad processors by todays standards.
http://ark.intel.com : if you really want to see how old they are and their specs.