pipelines big or small?

[abhishekit]

Alright, I want to get some basics about the pipeline. My confusion is..
Prescott has 31 stages, so although it has a higher clockspeed, per clock cylce it actually does less amount of work, even though it does it in less time. So why would it be fast?? I mean it would take more cycles to do the same amount of work, as would some other machine, say amd64 3200 in with 12 stages.
or is it just a showoff? increase your clock speed by increasing the stages in pipeline.
Can someone please enlighten me with teh basics..
Thanks

 

[spercharged69]

You're essentially asking someone to paraphrase a class on electrical engineering and processor fabrication.

I reccomend www.google.com

 

[gbojim]

This is a little old, but it provides a good basic understanding and is still perfectly relevant.

In fact, there is a lot of good info on that site explained in a very basic way.

 

[Mav451]

well i think about it more in IPC (instructions per clock)...well Athlon does more (yes all of the chips, starting from the slot A, Tbird, Thoroughbred, barton, and now 64) per clock.

Pentium has always done less.

I'm not Comp E. major and i don't intend to become one

The high number of stages means it can get higher clockspeed--i.e. they are trying to get the Prescott to 4-5ghz levels. In the same light, amd64 doesn't have to come even close to those clockspeeds, instead relying on high IPC's to do the same work.

Hehe, here's a picture. Imagine a line of people carrying water pails. The pentium has people in a straight line, carrying 4 pails of water. The athlon has 3 lines of people carrying 4 pails of water. The pentium line, however, moves alot faster, let's say 3x faster.

In the end, both can move the same amount of water. The cycles are the amount of pails being carried--AMD has a group of 3 compared to Pentiums single file line. AMD may get more done with each group, but the Pentium line moves faster much faster.

 

[abhishekit]

hey thanks all,
thanks gbojim..article was very good..doubt are very much cleared..