![]() If I need more cards I would be happy picking one of the top three depending on availability and postage charges. However even if you discard one of the tests (ie the Crystalmark under Windows) the top three are the same. How you judge the cards may determine on how relevant you think my tests are to real-world performance on the Pi.The SanDisk Ultra only stole 1st place from the Toshiba due to the big difference in Write speed on the Ubuntu test.The Kingston did badly in my “Ubuntu” test because the benchmarking utility threw an error with this card and I was unable to get any results.Why pay £7 for the Samsung EVO when the Toshiba is almost half the price? The cost of the card made no real difference to its performance.Some of the differences are so slight I’m not sure I would ever notice in reality. I would be happy to use any of them in my Pi projects. What my tests showed was that there is very little difference between the cards. Man:0x000002 oem:0x544d name:SA16G hwrev:0x2 fwrev:0x2Īveraging the ranks in all tests gives up the final ranking : Card Sync time dd if=~/test.tmp of=/dev/null bs=500K count=1024įinally I deleted the temporary file created by the above commands. To measure the read speed : sync echo 3 | sudo tee /proc/sys/vm/drop_caches To measure the write speed : sync dd if=/dev/zero of=~/test.tmp bs=500K count=1024 To read the card’s CID I used : cd /sys/class/mmc_host/mmc?/mmc?:*Įcho "man:$(cat manfid) oem:$(cat oemid) name:$(cat name) hwrev:$(cat hwrev) fwrev:$(cat fwrev)" The commands for doing this are documented in the RPiWiki. ![]() ![]() The final test was booting the card in a Raspberry Pi 2, extracting the device’s CID and then running some basic benchmarking. I ran this test using 100 samples/1MB sample size. The table below shows the results : The Ubuntu “Disks” utility includes a feature to “Benchmark Partition”. Official Raspberry Pi NOOBs 8GB, Class 10 As the checking involved writing over the entire card and then reading it all back I captured the read and write speeds reported after each test : ![]() Without checking using this tool you won’t be able to spot a fake card until it is too late. I only purchase SD cards from sellers I trust but I tested all five cards using H2testw 1.4 to double check. There are lots of fake SD cards out there. I used the same card readers and when I needed to use a microSD-SD converter I always used the one that came with the NOOBs card.
0 Comments
Leave a Reply. |