2013-04-20

A microSD Hero? Transcend 32GB Class 10 microSD memory card

After my mixed experiences with microSD cards of type SanDisk Ultra microSD cards (to put it mildly as one never knows whether the GoPro Hero 3 Black Edition will work or not with them) I am now trying Transcend microSD cards as an alternative. Transcend is claiming whooping 16MBit/s write performance ... yet another unsubstantiated claim?

Note: This blog article reflects my personal experience with particular consumer products. In no way this represents any recommendation. I'm not affiliated in any way with the companies mentioned, neither commercial nor private, with the sole exception that I'm just an ordinary customer.
As I returned two of my SanDisk Ultra 32GB cards after they failed in my two GoPro HD Hero 3 Black Editions to the shop where I had bought them, I invested my money immediately into another brand, this time made by Transcend.

Interestingly, two 32GB microSD class 10 cards in a double set costs almost 30% less than what SanDisk asks for its Ultra microSD cards. Now that's a deal, even more so as Transcends boasts 16MBit/s writing performance on its pack ... and now compare this with SanDisk that does not give any numbers at all except its incredible large reading performance. If they would go for subbits per hour, they would get even much more inflated numbers.

Alas, it's still the old question: how do these Transcend cards perform in reality? But after my experience with SanDisk it can't get much worse. From the famous GoPro forum (cheers, Rambo, you're doing a great job!) I knew already that these Transcend cards may most probably be okay, so I jumped ship.

2× Transcend 32GB microSD, class 10 package.

So let's go straight to the measurement: writing performance with 32kBytes block transfer size. This is assumed to be the block transfer size used by the GoPro HD Hero 3 Black Edition. Even as the Transcend card doesn't excel at real 6.6MByte/s, compared to the 16MByte/s as printed on the package, this performance still gives enough room for Protune performance requirements. And in contrast to SanDisk Ultras, the Transcend cards are comparable stable performers. The glitches that are visible should be covered for by the camera's internal buffering.

Now this looks promising for real HD Hero 3 Black Edition use.

Transcend 32GB microSD, class 10 writing performance
for 32KByte block size.

And indeed, several runs of these cards both above and under water were without any problems so far. No recording aborts as I saw them with the SanDisk Ultra cards. If this turns out to be stable in the long term, then these cards are a good alternative compared to SanDisk: better writing performance at a lower price, with enough room to the bare Protune requirements.

Well, as a compensation for the cards' better performance one of the SD card adapters was faulty. You can't get everything perfect in the same batch.

Coming back to the unsubstantiated claims topic from the beginning: of course, the marketing departments are on the safe side, thanks to their lawyers. Of course, there is some obscure benchmark they developed that churns out their impressive performance numbers. As if transfer block sizes of 512 kByte are realistic: the Transcend cards then reach whooping 14 MByte/s writing speed. Of course, dear reader, take all this with the necessary grain of salt and judge for yourself whether the claims made by these companies are true.