Fake Memory Chips Fake memory chips have become widespread, the reason is that unsuspecting buyers at on-line auctions buy them because they seem incredibly cheap and "offer great value" THEY DON'T ! Many fake memory devices have nothing like the memory the user expects to see, often they are described as 10x larger than they actually are. The customer is still deceived even when they plug it in to their computer or camera, because the size shows up just as expected. The people that produce these modify the internal parameters of the device so that they actually appear to be the genuine item.

The first indication of it being fake, is when all of a sudden the device fails, what is happening here is different in each case, but we bought one from an online auction site and tested it to destruction. What did we do? Well, it was nothing aggressive, or destructive. We wrote data to it, lots of data. Sure enough it failed after trying to store more data than the chips would hold. Well, we had ordered a 1 GB memory stick, and it only held 128 mb before failing.

Upon opening the device, we soon found out the reason. The physical memory chip would actually only hold 128 MB.

So why did it fail, and not just give an error message?

From a technical aspect, the vast majority of memory chips use NAND FLASH Technology. These are memory chips that have built-in wear levelling and have bad block re-allocation, similar to that in modern hard disks. The people that sell the fakes use specific brands of processor and NAND chips that can be easily reprogrammed to show a larger size then they can actually cope with.

So the problem is that, once the memory capacity limit is reached, further writes to the NAND beyond its capacity cause it to go into recovery mode. it thinks that there are bad blocks where it is attempting to write, and so starts allocating its spare sector pool. Once this is expired, the device will no longer operate and as far as the user is concerned, it is dead - no longer recognised by camera, computer, anything. The only way to get the data back is to remove the chips and perform a manual recovery. This is not as easy as it seems.

Because NAND uses wear levelling, the blocks of data are not in consecutive order, and so the block system used by the processor needs to be identified, the blocks put into the correct order, then the actual recovery takes place.

Why don't the manufacturers use technology that identifies when a write is out of the range of the memory chip.

Modern ones do, but the people that make the fakes are not going to use the modern processors as the parameters are harder to change.