Re: TF cards v MicroSD

On 22/05/2024 08:31, David Taylor wrote:

On 22/05/2024 08:10, nev young wrote:

Both bought from, and returned to Amazon.
and yes, of course, they could be fakes.
>
these :
https://www.amazon.co.uk/dp/B0BLSDMRSW?psc=1&ref=ppx_yo2ov_dt_b_product_details
>
and these:
http://nevilley.org.uk/tmp/Untitled.png
>
All of these cards do work and store the advertised amount of data.
Using Raspi imager as well as Linux program Disks to write/read/verify
64Gb images and run benchmarks, which do work but show very low
read/write speeds. (~9Mb/s).

 No chance the exFAT format is the problem?

No. They get re-formatted to EXT4 during the imaging process.

I've never used more than 32 GB cards.

I have 3 Pi using 64Gb cards without a problem. The rest use 8 or 32GB cards. I think they're currently all Sandisk although I have used some others (Lidl , Fuji , Samsung)

The slow speed is implied in the spec.

Cut from the ad --
▲Fast Transfer Speed - The Micro SDXC card adopts Speed Class UHS-I(U1) and Class 10(C10) and provides you with 80MB/s of read speed and 15MB/s of write speed, and supports full HD video recording. (The Performance may vary based on host device, interface, usage conditions, and other factors.)

 

I usually use SanDisk too but had run out of the 64Gb cards.
The 32Gb cards in use, in security cameras, are getting past 92% full on one of the cameras, hence me wanting a larger card.
--
Nev
It causes me a great deal of regret and remorse
that so many people are unable to understand what I write.