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X Speed Ratings: SLC vs MLC,?

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Probably, a thing related to speed ratings of SD cards is the SLC vs MLC issue. Although it is almost never mentioned by SD cards distributors, it seems the critical factor impacting access times, write and read speed, as well as the media durability. I'm absolutely not any kind of expert here, I just wanted to give a hint, hoping it's usefull for soemone more knowledgable. I can't say what is the link between 60, 133, 150x etc. ratings and the SLC/MLC, but there is something on here it seems. Or are the MLC not present on the market anymore?

Searching for "slc mlc sd" gives eg. this document: The Samsung SLC NAND Flash Advantage.

Compatibility section

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I think there should be a separate section on compatibility, e.g. between SD and MMC cards, the issue with 128 GB and larger SD cards, etc.

performance-loss with reformating

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In SDUC > exFAT filesystem, it is mentioned twice that one can reformat the card. It is however not mentioned that one needs to know the exact specs (like allocation unit size and erase block size) of an SD-Card to do so, or lose up to 50% performance. Said specs are usually not profided by the vendors, even if asked, you have to guess them with flashbench.

Bad article format

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The "History" section of this article is useless garbage, because it persistantly references terms and acronyms which are not defined until much later in the article. The article should be reformatted to move history to the end, so that the reader knows what the different terms mean. — Preceding unsigned comment added by 2601:589:300:C7C0:21A1:13AE:687F:5058 (talk) 20:03, 24 March 2024 (UTC)[reply]

Incomplete, or bad English syntax statement?

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The statement "Without they are guaranteed to at least reach A1 speeds", in the 16:11, 25 April 2024‎, version (https://en.wikipedia.org/w/index.php?title=SD_card&oldid=1220735921) of this article, doesn't make sense. The statement is found under the Speed section (section 3), Class subsection (subsection 3.2), "Application Performance Class" sub-subsection. Did the author/editor perhaps mean to write something like "Without host driver support, A2 cards are guaranteed to at least reach A1 speeds"? Mercy11 (talk) 10:05, 26 April 2024 (UTC)[reply]

SD 7.0 does not support UHS-II/IIIcards

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SD Express cards cannot support UHS-II interface. SD7. 0 and SD7. 1 define full size SD and microSD form factors using two power supplies, a traditional 3.3 volt and 1.8 volt. 112.104.98.124 (talk) 08:33, 9 October 2024 (UTC)[reply]