Last week I ordered two Samsung Class10 32GB microSDHC cards on ebay which turned out be product fakes. What could have been only an annoyance quickly turned into a disaster as only 6.9GB of the 32GB were usable. Writing more data to the card would result in data loss.
First, some pictures of the packaging which appears to be genuine at first glance.
In retrospect, there are, however, a few oddities that might have immediately been observed by a keen eye:
Advertised as a Class 10 card, a write speed of 7MB/s should cause a lot of suspicion. Per definition, a Class 10 rating means a sustained read and write speed of 10MB/s.
From what I gather, all genuine Samsung cards should be “Made in Korea”.
This is what the package of the original product looks like:
As I inserted the card into my PC and started copying some files to it, I immediately noticed the abysmal writing speeds of only about 3-4MB/s. When later the files would not work in the device, I checked the card using the excellent H2testw utility (output in German translates to “defective device, 24.2 GB data lost”):
Der Datenträger ist wahrscheinlich defekt. 6,9 GByte OK (14626551 Sektoren) 24,2 GByte DATEN VERLOREN (50882825 Sektoren) Details: 0 KByte überschrieben (0 Sektoren) 0 KByte leicht verfälscht (< 8 Bit/Sektor, 0 Sektoren) 24,2 GByte mit Datenmüll (50882825 Sektoren) 0 KByte mehrfach genutzt (0 Sektoren) Erster Fehler bei Offset: 0x00000001be5dee00 Soll: 0x00000001be5dee00 Ist: 0x19f1b29c55f885b4 H2testw Version 1.3 Schreibrate: 3,55 MByte/s Leserate: 12,0 MByte/s H2testw v1.4
Taking a closer look at the card revealed the product number MMB3DO8BUACA-GE:
Coincidentally, the same number was found on a fake SanDisk microSD card (which also was pretty much the only useable Google search result for this number, no results whatsoever on any Samsung site).
Bummer. Return to sender.
A word of warning
Fortunately, I copied more than 10GB of data (in my case Openstreetmap files for use in a GPS device) to the card and therefore noticed the problem right away when the maps would not work.
Just imagine using one of these cards in a camera and clicking or filming away only to learn that most of what you shot turned to garbage instantly.
Thus, when in doubt, always check your flash media using H2testw.
I found two accounts of the exact same fakes on YouTube (64GB instead of 32GB cards):