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Comment by numpad0 | Hacker News Reader

SD in itself isn't technically unreliable. Lots of smartphones do just fine with eMMC, which is same thing as microSD card except in nonstandard IC chip form thus can't carry SD branding.

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Practically they end up being really different. SD Cards end up being bottom of the barrel flash chips (even from the 'good' brands), whereas eMMC uses flash good enough that you can count on it being non replaceable.

You want "industrial" cards from a vendor tailored to the space. I wouldn't trust even those new industrial sandisk cards.

Yeah as someone who has deployed SD-based and eMMC-based systems in industrial spaces, SD cards are hot garbage compared to eMMC and I would strongly recommend not using them in anything that needs to be reliable.

There should be a market for people who will pay extra for SD cards that:

1. Absolutely don't lie about their capacity

2. Have a reasonable MTBF

3. Are reliably fast

But instead we're all dealing with an industry that raced to the bottom years ago.

I'm concerned that the same mentality will infect the eMMC market eventually and it will become impossible to find quality parts after a couple of years.

What you're asking for does exist in the industrial market (and I'm skeptical of those 'industrial' branded sandisk cards). They still use pseudo SLC (storing one bit in every flash cell as 00(0) or 11(1) and correcting up or down on read back). They also will work with you so you can track BOM changes as they internally change the cards so you can track failure rates. They also give you access to tons of internal perf counters so you can do preventative maintenance (ie. swap the card if it's getting long in the tooth). They also just generally treat you as a business partner rather than a consumer, wrt support and what have you.

It costs a pretty penny though. $40 for a 2GB non micro card was the last quote I got.

Worth it if you're installing something like a Raspberry Pi in a ceiling mount screen that's a pain to access.

Technically it should be the same. In practice manufacturers make certain assumptions.

1. most SD card devices are battery powered

2. SD card failure is acceptable because they are replaceable

3. SD cards are not used as main storage for a computer

That leads to low quality SD cards.

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