What in nm when we are talking about processors?

[PikaPika]

I've been Googling and found 2 common explaination.

1. It is the distance of the transistors from each other on the die (What's a die? I assume is the chip made with nm technology?).

2. It is the size of the transistors.

All I know for sure is the smaller the nm means more transistor can be used, energy consumption is higher and higher clock speed can be achieved.

 

[AdrianPerry]

nm means "nanometre" which is basically a measurement. It's a very very small fraction of a metre. So your first description is accurate.

Smaller does generally does mean quicker and more efficient in terms of chip-size/CPU efficiency. They are packing more power into a smaller space with less distance for information to travel.

 

[popatim]

Neither of those definitions is very accurate at all. Sorry.
When discussing the nm of a cpu you are talking about the lithography technology being used. With a 32nm process transistor gate lengths could be as small as about 12nm (i'm not going to do the math LoL) but what it is referring to is Half the distance between Identical compnents of memory cells in the cpu itself since the size of those dont deviate much so you see they do take the size of the cell itself into the measurement. Like measuring from the leading edge to the leading edge.
I hope this clears it up somewhat.