SD Cards Up To 128TB And 985 MB/s Coming With NVMe and PCIe Interfaces

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TJ Hooker

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Soon you will be able to purchase SD Express cards that support up to 985MB/s of throughput courtesy of the new SD Version 7.0 specification.

This seems like the maximum theoretical throughput of the interface (985 MB/s is simply the speed of a PCIe 3.0 x1 connection), which may or may not bear any similarity to the actual speed of the storage. Kind of like how you could say SATA 3 HDDs "support up to 600 MB/s of throughput", but actual speed is limited by disk I/O.

Similar case with the size of 128 TB, just the max size supported by the spec and not indicative that we're going to see SD cards that big any time soon.

Just thought I'd clarify in case someone read that and thought they'd actually be able to buy an SD card that's 128 TB and/or has 1 GB/s read/write speeds.
 

USAFRet

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They will be available on ebay next week.
Just like the $10 128GB USB sticks are already.

:no:
 

AgentLozen

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@TJ Hooker

The stuff that you mentioned is what would have tripped me up years ago. I remember when SDXC was first announced and I was expecting 2TB SD cards to come out soon. Thank you for the clarification.

Edit: I just reread this post and it sounds like it could be sarcastic. Rest easy, I'm being genuine.
 

alextheblue

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That chart deliberately leaves out UHS-II and UHS-III, to make SD Express look miles better than existing standards. I support SD Express but that is just sad.

the new SD Express specification is also backward compatible with the legacy UHS-I interface.
Yes, with a "but". If you stick a NEW SD Express Platinum Turbo card in a UHS-II or UHS-III device... it will run at UHS-I speeds. This makes perfect sense given their desire for backwards compatibility, as they have to use the UHS-II/III pins for the PCIe link and keep the legacy (UHS-I and older SD) pins intact for backwards compat. However it is a bit counter-intuitive for the average person. They may not understand that a "faster" SD Express card is actually slower in a UHS-II/III device than a "slower" UHS-II/III card.

Also backwards compatibility isn't guaranteed, especially as capacities increase. But by that point we should all pretty much be on the new interface or perhaps even a successor. SDE-II... repurpose the legacy pins for another lane?
 
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