The Samsung 840 Non-Pro SSD we are reviewing today is not based on a SandForce or Marvell controller, but, instead, on Samsung’s own creation, the Samsung MDX (S4LN021X01-8030), which is a triple-core ARM microprocessor. It’s the same controller used on the faster 840 Pro; the main difference between both series is that the 840 Pro uses MLC flash chips (2 bits per cell) whereas the Non-Pro uses TLC chips (3 bits per cell).
As the name suggests, TLC stores three bits per cell which increases its density compared to MLC (two bits per cell), and SLC (one bit per cell). This means that the price per GB of flash storage will go down significantly, which enables new SSDs to be built at unprecedented price levels. On the other hand, TLC flash is slower and comes with shorter endurance, too, which means firmware has to be running at its best to avoid any potential issues.