What makes a low-power consumption CPU?

[SaltyFish]

What exactly goes into low-power consumption CPUs (e.g. Intel's Atom and AMD's Puma) that makes them such? Sure they're clocked lower than the standard desktop CPUs. But clocking down a desktop CPU isn't going to get anywhere near the same power consumption.

 

[RCoon]

The die is generally tiny, transistor count for one.
e.g. 2008 atom has 47 million, 2008 i7 has 731 million. Imagine the amount of power difference such fewer transistors have.

 

[Frag_Maniac]

Mostly it's die shrinkage. It has to shrink since transistor count and overall CPU complexity is going up. Thin silicon wafers means much smaller circuitry and transistors, which require less voltage to run.

The smallest is Graphene, which is basically shaving carbon fiber down to 1 molecule thickness. It has inherent problems though.

 

[Beertintedgoggles]

A better way to approach this concept would be to ask, "How can you lower the power consumption of a transistor?" There are some good reading materials if you just search that phrase in google. Here is an older but still pretty good description of a few of the issues:

http://www.google.com/url?sa=t&rct=...oIyJOqnGty0QKDrUT2hLMbA&bvm=bv.75775273,d.b2U