Why is it better for cpus to be smaller?

[jinduy]

just curious as cpus get smaller and smaller.

is it a power consumption benefit?

 

[Sheninat0r]

Well, die size will vary as process nodes get smaller but more and more transistors are added. Lower process nodes give us lower power consumption and less heat generated, I think. That, and the ability to put more transistors in a given area, thus increasing performance.

 

[veri745]

The main reason to reduce the die size is cost of manufacture. Smaller die means more dies/wafer means more revenue/wafer.

 

[fffblackmage]

just think how big the cpu would be if we were still using the old manufacturing process back in the pentium days. Instead of a few million transistors on a 300mm^2 die, we have a monolithic 1 billion transistor, 60,000mm^2, cpu. Though probably not impossible to make, it would be incredibly expensive, not to mention it probably won't work anyways.

 

[polarbear6]

well, think of a room that your gonna use only for cabinets and wardrobes..
would you prefer a wardrobe which unnecessarily hogs up the space and not allowing you to use its volume to 100% ?? or a wardrobe which is smaller in size but you can atleast use 90% of the space.

Now comming to chips let us take the example of the wardrobes, let us assume that we are living in alaska and you simply can't wear clothes from your wardrobe if they are at the room temperature.so you have to perpatually heat them.
so more the volume more will be the heat consumption.

and comming to manufacturing, the bigger the wadrobe the bigger will be the raw material's cost !!!

remember with a die shrink, they are also changing the die also. they are better organising the transistors !!!
like the i7 and core 2 quad !!! both are of the same die size but are different !!!

 

[BonzaiDuck]

I didn't train in the disciplines for CPU design; I was involved in the more practical application of software and database management.

But -- yes -- shorter distances between components mean more speed, less power, less heat dissipation. That's my understanding of it. One engineer who worked for Intel (and dropped out) told me that it was "getting down to the mol-e-cular level!" What's the speed of light? How fast do electrons move on a silly-cone wafer?

This sort of puts the kibosh on application of TEC cooling, except for having heat dissipated across the same size heat spreader. TEC becomes less and less effective for thermal wattage exceeding 65W. Its effectiveness requires some amount of surface area.

Does anyone ever even remember the age of computers before Steve Jobs and minicomputers like the DEC PDP? there was once something called an IBM 360. As I understand it, that machine and its predecessors occupied rooms and needed massive air-conditioners. And before I acquired my first PC, the IBM 370 at the old HEW Data Management Center (in DC) had (gee whiz!) 10 . . . .Megabytes of memory . . . . shared with hundreds of terminals located in three four-story buildings. . . .

How it was . . . . "in the day" . . . .

 

[taltamir]

1. power consumption is lower.
2. heat generation is lower
3. as a result of 1 and 2, clockspeed (mhz) can be pushed higher.
4. the chance of a defect being on your chip is lower (resulting is less wasted chips due to defects...)
5. More chips can be made at once.
6. You can increase the amount of transistors while maintaining feasable die size (aka, something small enough to put in a chip, and not have a defect)

A very large die like the ps3 cell chip is likely to have a defect, so they had less than 20% of dies being "working"... and those 20% each had ONE of the 9 cores disabled (due to a defect)... so it was so BIG that EVERY die had ONE defect ruining one core.
the AMD phenom2 X3 has a defect ruining one of the four cores. the phenom2 X2 has two defects (or more) ruining 2 of the 4 cores.
The smaller your die, the less is "wasted" per defect.

 

[Cookie Monster]

@OP

It depends on what you mean by the word small. If you were referring to the physical size of the CPUs hence its die size, then its better to have small chips because you would be able to fit more chips per wafer (looks like veri745 beat it to me). However a physically smaller chip doesn't mean it will consume less power and produce less heat compared to a physically bigger sized chip.

I guess you were referring to transistor size which does have a huge impact on power consumption, but I had to nit pick anyway