3 Replies Latest reply on Aug 12, 2017 4:52 PM by etl

    TR 1900X internals


      I would like to know the Internal configuration of the TR 1900X a 8C/16T CPU.

      Is it:

      1. 2 cores per CCX for both dies,
      2. One full 4 cores CCX per die,
      3. One 2x4 cores on one die the other die only delivering memory ports and extra PCI-E ports?


      Thank you.



        • Re: TR 1900X internals

          To extend on the original post let's details some pros & cons of the three core-layouts.


          Threadripper 1900X 8 cores - 16 Threads 4 memory channels.

          One 16x PCI-E per die + 16 PCI-E lanes in a mix of (8x,4x) configuration.



          Layout possible:


          1) Two cores per CCX, 4 cores per die


               +: 4 x 8 MB L3 caches

               +: Thermal spread

               +:    Recycle die with defective core(s) on both ccx


               -: Increased average latency for thread to thread access.


          2) One full 4 cores CCX per die


               +: Task in the 4-8 threads ranges.

               +: Driving dual HSA compute task with one GPU card attached to each die.


               -: 2 x 8 MB L3 caches.


          3) One full die (i.e. both CCX fully populated) and one die providing extra memory channels and PCI-E lanes.


               +: Task in the 8-12 threads ranges: Keep the core to core latency low

               +: Balanced CPU-GPU HSA compute task with one GPU card attached to each die


              +-: The non uniform ressources repartition might be and advantage for some applications

                  that require large amount of memory or will use the PCI-E lanes, on the die empty of core, for SSDs. 


               -: 2 x 8 MB L3 caches.


          At first glance it seems that option 2 might be the most balanced one overall.

          As the process mature and yields increase the ability to economically reuse die with defective cores on both CCX

          will diminish.