Anyone know how many pipeline stages the Pentium M has. I'm writing a report for one of my classes, and have only been able to find that it is between 10 and 20. A source will be needed as well.
"Somewhere between 10 and 20 - Taking a cue from NVIDIA, Intel isn't revealing exactly how deep the Pentium M's main pipeline is. They have said that it's deeper than the Pentium III's 10-stage pipeline, but shallower than the Pentium 4's 20-stage pipeline. A deeper pipeline does help enable higher clock speeds, but it also increases the penalty for branch mispredictions. The Pentium M aims to avoid branch mispredictions as much as possible using a swanky new branch prediction unit. "
LeonardoWake up and smell the glaciersEagle River, AlaskaIcrontian
edited May 2004
Well, I certainly don't know the number, but it's not a long pipeline like the P4s'. This statement of mine is based merely on my limited exposure via my office's two Centrino-based laptops. Although they are only 1.2Ghz (maybe 1.4?) models, they will run rings around our older Dell P4 1.6 desktops. There is just no way they could have a long pipeline with only 1.2GHz and be as snappy as they are. Hmm, guess Intel took a page out of AMD's manual on the Centrinos. Whatever the source, they are very good CPUs.
An astute observation Leo, and a well-reasoned conclusion. That's exactly how I came upon my guestimate of 12 stages, for 20 is much too long for efficient operation, though it is not the P3's 10 by any means, for the top Centrino is too fast for a 10 stage pipe. The Athlon's is 12 stages, and I believe the A64 is 14 stages.
Comments
http://www.techreport.com/reviews/2003q3/pentiumm-1.4ghz/index.x?pg=1