In message 
          bob oing  wrote:

> Some months ago I bought a Samsung Evo + microSD card as a boot
> device for an RPI3B (under FreeBSD-current). Initially it seemed
> as fast or faster than Sandisk Extreme cards used previously.

> Lately, it's become extremely slow. At first I thought it might be
> FreeBSD's fault, but now I'm starting to wonder if the card is the
> culprit.

> Has anybody observed similar behavior under Raspbian?

> Thanks for reading,

> bob prohaska

Maybe OTT, but...

I bought four 64GB Samsung Evo+ on eBay (stupid, I know) and they were ALL
fakes, but their packaging was convincingly genuine. They were extremely
slow putting an OS on, and had announced themselves as 67GB. Using fsprobe
(Linux, but based upon Windows h2testw) they were all below 16GB - their
controllers had been tampered with. Doing a Benchmark using an SDcard
reader via UbuntuMATE gave most revealing graphs which were far from
normal. The seller was confident that I was bluffing, and refused to give
a refund unless the cards were returned. A challenge via eBay did nothing,
but one via PayPal went uncontested, so I got my money back. An
unfavourable review on eBay, repeated several times, never got published.
Caveat emptor...


--
Mark J
From RISCOS 5.25 on a BeagleBoard-xM and Raspberry Pi2B
- and Linux on a PandaBoard ES and Raspberry Pi3B

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