Currently the flash memory most used is Nand MLC able to store two bits per cell. This is what one finds in USB keys and SSD discs. In order to gain in capacity, the manufacturers want to use a memory able to store 3 bits per cell; this will increase the capacities by 50% for a small cost overhead. According to Digitimes, all is not well with this X3 memory. At least certain chips using this technology have been returned to their manufacturer for problems of stability. We do not know the details of the problems, but they are probably related to errors rereading the recorded data, each cell having more energy levels. We hope that these problems are only temporary, if not, we will know at the beginning of 2010 as this will act as a brake on the increase in capacity of flash memory. This does not relate to the SSD, this memory not being reliable or fast enough for this type of use.
