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does the 2200g have less cache because of graphics part?

Discussion in 'CPUs' started by ExoMale, Jan 11, 2019.

  1. ExoMale

    Mobster

    Joined: Jan 9, 2016

    Posts: 3,160

    Location: Gloucestershire

    just comparing it to my 1200 again and while the APU has higher clocks it has lower cache which i know is important, why is that?
     
  2. DragonQ

    Soldato

    Joined: Jun 13, 2009

    Posts: 5,918

    Each Ryzen CPU has a single die with two CCXs that house up to four cores each, so an R5 1500X will have 2 cores per CCX. A Ryzen APU has a single die with one CCX and one graphics core, so an R5 2400G will have 4 cores on a single CCX.

    Each core has 0.5 MiB of cache and each CCX has up to 8 MiB of L3 cache, so each configuration will have 4 x 0.5 = 2 MiB of L2 cache, but if there's only one CCX it can only have up to 1 x 8 = 8 MiB of L3 cache. With two CCXs there can be up to 2 x 8 = 16 MiB of L3 cache (e.g. all 6 or 8 core CPUs).

    The R5 2500X is basically an R5 2400G with a disabled/broken graphics core and it has the full 8 MiB of L3 cache available. However, the R5 2400G only has 4 MiB of cache so half of it has been disabled.
     
  3. Armageus

    Don

    Joined: May 19, 2012

    Posts: 9,181

    Location: Spalding, Lincolnshire

    The "APU" parts e.g. 2200g use just 1 CCX module rather than 2 as used on the normal Ryzen parts (4 for Threadripper). This is purely from a space point of view, as the graphics die takes up the space that would be occupied by a 2nd CCX.


    A CCX has either 4Mb or 8Mb L3 Cache (possibly all have 8Mb physically with some fused off to improve yields but this hasn't ever been confirmed afaik)

    On e.g. a 1200 each of the 2 CCX's will only have 2 cores enabled (e.g. because the others may be faulty), thus improving yield and profitability, whilst using L3 cache from both CCX modules (so 4Mb on each for a total of 8Mb)

    The 2200G only has 1 CCX and consequently only has one L3 cache module available