Tuesday 24 September 2013

Test your SD memory cards (and USB Flash drives)!

I recently ordered a 32GB Class 10 micro-SD card from a UK seller on eBay (electronicmemory) and it arrived in the post 2 days later.
The first thing I do whenever I buy a new Flash drive or SD card is test it using RMPrepUSB - Quick Size Test. I wrote this test specifically to test for 'fake capacity' memory devices.
Fake capacity memory devices  are created by doctoring the controller firmware which has been deliberately altered to lie about the capacity of the memory. The SD card was only £8.99 and I had my doubts when I purchased it, mainly due to this text at the very bottom of the item description:
'When these brand new Micro SD cards devices have been tested they vary in storage capacity, but are all listed as good and are from 4GB UP TO 32GB.
 The same as pretty much all cheaper micro sd  memory on e-bay, they just don't tell you this.  
Please note that whilst these cards are brand new and have been shipped to me straight from the factory they are sold as upgraded cards and therefore the capacity and speed may vary for each card, (They may experience read/write errors once max capacity reached - The one I have in my phone is up to 4GB at the moment with no issues) hence the very low price and free 1st class delivery! Approximately a third of what you would pay for brand new perfect condition products. Once you receive your card it is always recommended that you format it in your device before use.'

So the devices have been tested and are 'good' (the pack was unopened when I received it!). It is advertised as 32GB and it is not at all clear if this is a 32GB card or what!
Apparently, it is OK to advertise a 32GB card but supply fake SD cards that really are only 4GB!

Another eBay advert from a differrent seller states:
All cards are tested with results ranging from 4GB to 32GB in capacity. These are offered as upgraded cards, therefore the speed and capacity will vary with each card. Errors may be experienced once the maximum capacity has been reached. We suggest formatting the card in FAT32 format if problems occur'

Again, it seems it is fine to sell deliberately faked cards! How many cameras would format a 32GB card as anything other than 32GB! Cameras don't run a size test on the card to see if it is fake!

The Quick Size Test in RMPrepUSB (3rd button up on bottom-right - see below) took just 5 minutes to run (it would have been quicker if it wasn't faulty!). Note: It is a destructive test and so you need to format the memory after the test has passed. Here is a screenshot of the result I got on my '32GB' SD card (click to enlarge):

The UK seller offered me a full refund, but that is not the point! The seller is knowingly deceiving the public (he even admits it in the small print!). It is like being paid by someone with a counterfeit £20 note and then when it is pointed out that the note is counterfeit, saying 'oh yeah - sorry - here have a real one instead' and then they are allowed to go away free! Since this seller had 10,000 sales, I hate to think how many people he has conned into thinking that they were 'unlucky' and that the memory must have been 'faulty'! It is not 'faulty' - it has been deliberately faked in order to deceive you and once you fill it up past 3.8Gb it will totally corrupt all your precious photos!

The worrying thing is that these sellers seem to think it is OK to sell fake memory as long as they mention in the small print that they are 'upgrades' - whatever that means (reprogram them and stick a 32GB label on them perhaps?). The memory that they use in these products is usually reject memory too and so even the 4GB part that works could lose 'bits' at any time - they get this memory from the reject bins at the back of the memory chip factory - after all, if the chips were any good then they would be sold as 4GB memory chips by the original manufacturer and branded correctly!

One eBay advertiser even tries to explain that the memory compresses the data and so even if it formats as 4GB it actually can hold up to 32GB of data! Utter twaddle!

'electronicmemory' is still happily selling these fake SD cards today - even though I pointed out to them that these cards were fake and had been deliberately manufactured to deceive! They could 'legally' advertise them as '4GB SD cards pretending to be 32GB' in the subject title, but they choose to advertise them as '32GB SD cards' and add some 'doublespeak' in the text right at the bottom of the ad instead. What conclusions about the seller can we draw from this?

If you come across any similar companies selling fake products on eBay, please report them to eBay as selling counterfeit goods using the link on this page (use the Be sure to report listings that offer counterfeit items or replicas. link).

The Quick Size Test in RMPrepUSB is quick to run (unlike H2TESTW which takes hours) - so there is no excuse for you not to run it. Test your SD cards and USB Flash memory sticks NOW and remember to test any new ones as soon as you get them. If they fail, ask for your money back immediately (before the eBay time limit expires!), then give negative feedback (if you haven't already left +ve feedback!) and report them to eBay.
If you don't check your memory devices, you will lose all your data/photos when you least expect it!

Note: I have also written FakeFlashTest, which has a simple interface and two test options:
1. Quick Test - This is the same test as in RMPrepUSB (but improved/faster)
2. File Test - this is a similar technique to H2TESTW (i.e. non-destructive), it fills the unused filespace with large files, but is much quicker.



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