Quality Concerns For Kingston microSD Cards
Andrew "bunnie" Huang, whom we've discussed before for his book on Xbox hacking and development of the Chumby, has made an interesting blog post about problems he's found with Kingston microSD cards. He first encountered a batch of bad cards during production of the ChumbyOne, and found Kingston initially unhelpful when trying to get them replaced. After noticing some unusual markings on the chips, he decided to investigate for himself, comparing the ID data and dissolving the cards' casings with nitric acid to take a look inside. He found that each of his Kingston-branded samples actually had a Toshiba/SanDisk memory chip inside, and that the batch of low-quality cards he received may not be as uncommon as he thought.
"Significantly, Kingston is revealed as simply a vendor that re-marks other people's chips in its own packaging. Every Kingston card surprisingly had a SanDisk/Toshiba memory chip inside, and the only variance or 'value add' that could be found is in the selection of the controller chip. ... This tells me that Kingston must be crushed when it comes to margin, which may explain why irregular cards are finding their way into their supply chain. Kingston is also probably more willing to talk to smaller accounts like me because as a channel brand they can't compete against OEMs like Sandisk or Samsung for the biggest contracts from the likes of Nokia or RIMM. Effectively, Kingston is just a channel trader and is probably seen by SanDisk/Toshiba as a demand buffer for their production output. I also wouldn't be surprised if SanDisk/Toshiba was selling Kingston 'A-' grade parts, i.e., parts with slightly more defective sectors, but otherwise perfectly serviceable. As a result, Kingston plays a significant and important role in stabilizing microSD card prices and improving fab margins, but at some risk to their own brand image."
"Significantly, Kingston is revealed as simply a vendor that re-marks other people's chips in its own packaging"
And that is a surprise because? Of course that's what Kingston does - they don't own any fabs.
It's becoming highly unreliable. Advances in error correction are plugging some of the holes, but you can expect to start to see real problems soon, especially with cheap brands where they don't up their controller quality (the controller has the ECC) to compensate for the low-grade NAND they buy.
As to Bunnie, I was pretty sure he'd been around the block already. Of course Kingston just repackages other people's NAND chips. There's only something like 7 manufacturers of NAND, and even that counts Intel and Micron separately even though they both sell the same designs every time. What did Bunnie think was in iPhones and XBox 360s? Apple and Microsoft don't make NAND either!
http://lkml.org/lkml/2005/8/20/95