Along with Samsung's release of the 840 Pro SSD today, Samsung is also releasing a more mainstream oriented 840 SSD. It's based around the same Samsung MDX controller as the Pro series, but uses 3-bit-per-cell (TLC) NAND instead of 2-bit-per-cell (MLC) NAND found in the 840 Pro. The 840 Pro also has a firmware which is tuned for heavier workloads consisting of more writes and random IOs, whereas the 840 is designed more towards read centric (i.e. consumer) workloads.

Samsung is actually the first manufacturer to publicly release a TLC NAND based SSD, so we will have very interesting time testing it. Remember, adding more bits per cell reduces endurance and also increases program, erase and read latencies. In a Q&A session Samsung couldn't tell us any exact P/E cycle numbers, but they claimed that the 840 has higher endurance than many competitors MLC based SSDs. We didn't get more specifics than that, but we hope to be able to test this as soon as possible. As for the performance, Samsung again wouldn't tell us any raw latency numbers, but they said their TLC NAND is roughly 50% slower than their MLC NAND. For a more in-depth look at the architectural differences between MLC and TLC, refer to our Understanding TLC NAND article.

The regular 840 SSD will be available in capacities of 120GB, 250GB and 500GB. The increased amount of spare area makes sense given the use of lower endurance TLC NAND. The 840 will be available as a bare drive or in a notebook kit, which adds $20 to the prices in the table. Both, the 840 and 840 Pro will be available on October 15th.

Samsung only provided 256GB 840 Pro SSDs for reviews, so unfortunately we haven't been able to test the 840 yet. However, I should get our review sample later today and hopefully some other capacities of the 840 Pro as well.