So when I buy a new SD card, USB drive, etc, the first thing I do is test it to make sure it’s working fine.
I bought a 6-pack of 64GB microSD cards, and tested them all with f3.
All of them passed except for one.
So the method is simple enough. You put in the card and you fill it up with data using
f3write, and see how that goes:
In this case, it wrote well enough, and filled up the card. This is also a great way to measure the speed of the storage.
The next step was to verify the data was written properly using
f3read. And this is where it ran into trouble.
Right away you can see it had a bunch of corrupted sectors. And by the time it got to 32GB or so, it completely crapped out and just stop reading.
So out of 6 cards, one is unusable. I wonder if I can get a partial refund.