@jazzbiker: In the past two months, we've ordered a few dozen 512GB flash based devices (SD cards, MicroSDs, USB sticks, etc.) from numerous vendors. Our local hardware store (55+ minute drive... and I call it local) sells these cards legitimately for $35 and the quality is reasonably solid. Some of these "fake" vendors will go as low as $11 USD for a 512GB, I'm guessing with the mentality of "...stealing $11 is better than trying to get $30 and having fewer victims!" so even though there's a slight chance of financial loss, I've paid $11 through $28 for many different China brands and
every single one of them is a fake. In fact, only one China chip was what it claimed to be... but it claimed to be 400GB.
400GB isn't "a thing."
More than likely, it was SUPPOSED to be a 512GB but the die likely cut quite a few rejects where 400 of the 512 was usable... so technically they're defective but they passed testing!
Now, to make fun of the problem, these same "fake" vendors are using
naive shoppers as their newest victims by hacking old 1GB and 2GB SD cards and selling them as
128MB, 256MB and 512MB... most people don't "realize" that "MB" hasn't been manufactured in YEARS and it's not the size you're after, but these MB cards are selling like hotcakes because they have the right
NUMBERS ("...my son told me to buy a 256...") and the hacks are LEGAL (if you buy a 512MB card --- you're GETTING 512MB!) so resellers, banks, credit card companies, etc. aren't as willing to approve charge-backs/refunds as you end up getting exactly what you purchased, even though you just paid $25 for a 256 MEGAbyte SD card!!!
does the problem really worth so much efforts?
Sometimes.
Isn't it enough to fill the drive with any non-repetitive sequence and then verify it?
To fill an SD card of 512GB at ~25MB/s... I'm guessing that's about six hours of just writing to the card, another 3-4 hours verifying the data ~40MB/s... all for a $35 card that I know where I can get legitimate ones... but
our clients don't. Their friends and family... they probably do not as well. If I educate just ONE client, there's a possible impact of 20 or more people. If all of them were "informed consumers" that's potentially HUNDREDS of dollars saved from theft.
Most clones/fakes start at 128GB these days, but there are plenty of the smaller ones still in circulation. Plus, there's the MB issue, too.
We hunt down the bogus "brands" and where they can be purchased from and we find legitimate ones in the process. Sharing this information doesn't put the bad guys out of business, but if enough people know how to look for problems, that's $XXX.xx the bad guys
aren't making!