• Victor@lemmy.world
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    7 months ago

    Megatransfers? Or what does the T stand for? And how does a “transfer” (if so) translate to bytes?

    • bonus_crab@lemmy.world
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      7 months ago

      Yeah mega transfers. 1 transfer is 8 bytes. the DD in DDRX is double data so it can send 2 transfers per channel per clock. CPUs pretty much always use 2 channels, so the formula is just GBps = 32 * MT/s. My PC has 6000MT/s DDR5 in a dual channel config so thatd be 192GBps.

      Idk how apple is getting above 300GBps, maybe theyre counting the integrated GPU as part of the total. GPUs often have 4 or 6 or 8 channels so thatd make sense…

      • Victor@lemmy.world
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        7 months ago

        Thank you for going into detail.

        Okay so, 1 T = 8 B. DD => 2 T/channel. And with 2 channels we get 4 T, so 4 × 8 = 32. Okay I get you. Thanks so much. 🙂

        Yeah that’s a crazy number with 300-500 GBps if DDR5 is doing around 200… Absolutely insane actually. But yeah, good theory about the GPU. Those bastards, padding the numbers.