Customer Review

Reviewed in the United States on March 11, 2019
Summary
- 1kB sustained: 10 MB/sec
- 4kB sustained: 12MB/sec
- 1MB burst: 22MB/sec
- 1MB sustained: 13MB/sec

Whenever new large capacity cards are released on the market, I am always concerned with scammers taking advantage of people and slapping a label on a smaller card. When I received it, I tested the card with a simple script that create 360 1GB files in 1kB blocks, like so:
`for i in $( seq 1 360 ) ; do dd if=/dev/zero of=sd-text-${i} count=1048576 bs=1024 ; done`
One of the main thing I'm testing for is insuring that the card isn't 128GB ro 256GB in this case, because very few people will actually take the time to do so, stick the card in their phone/camera/game console and find out they run out of space early than expected when it's too late.
I'm happy to report that though it took a really long time, the card has now 386 GB of test data.
It wrote at 10.468 MB/s on average with a standard deviation of 1.166 MB/s.
This is a known torture test because small blocks challenge the way the underlying flash is organized.

A more realistic test would be to write in 1MB blocks in bursts of about 20MB which most cameras do for example (they typically buffer up and then dump their buffer to the SD card, which why for example burst photos are faster in the first second or so)
This test yielded a speed of 22.641MB/sec

I hope this helps
review image
25 people found this helpful
0Comment Report abuse Permalink

Product Details

4.7 out of 5 stars
4.7 out of 5
41,677 customer ratings