Today's Hard|Forum Post
Today's Hard|Forum Post

Samsung 840 Series 500GB TLC SSD Review

Samsung has released the first TLC NAND equipped SSDs into the market, creating the lowest price points we have witnessed for SSDs bringing large capacity SSDs within reach for average users. Today we test the 500GB TLC Samsung 840 Series SSD to test the performance in steady state of a large capacity TLC Solid State Drive.

Samsung 840 Series TLC 500 GB Basics

Samsung's 840 Series has shaken up the SSD market by bringing TLC NAND into the wild. This type of NAND holds more bits per cell, effectively increasing the amount of data stored in the same amount of NAND. This increase in density, paired with process shrinks of the NAND, has created a much cheaper price point for consumers.

We have already reviewed the 250GB TLC Samsung 840 Series and the 256GB MLC Samsung 840 Pro, but the interesting nature of the new TLC NAND brings us to this testing of the 500GB TLC Samsung 840 to illustrate TLC SSD performance scaling.

The price of a 500 GB TLC Samsung 840 is only $349.99. This is a remarkable price of only 70 cents per GB, and an unheard of price only a few months ago. For this capacity point the price is unmatched, with most competitors not even coming close to the price of the Samsung TLC SSDs. While there are some trade-offs in endurance and speed, any SSD will be a huge increase in performance over even the fastest HDD available. The increase in the response times, resulting in a tangible snappy feeling during everyday use, is simply unmatched by HDDs.

This type of value for consumers is the driver behind the eventual proliferation of this type of NAND into the marketplace. Samsung is leading the way with the world’s first TLC SSD, but the rest of the industry is already working on SSDs featuring the TLC NAND. We have been testing a steady stream of new SSD controllers in recent months, and one common theme has been the inclusion of TLC compatibility in the specifications. The introduction of more TLC SSDs will be coming in the next few months, which should help to bring prices even lower.

The introduction of TLC into consumer SSDs does come with some trade-offs, particularly in endurance and speed. Due to the increased number of bits stored per cell the programming and erasing of the TLC NAND cells is much more strenuous, resulting in a markedly shorter lifespan of the underlying NAND. This type of NAND would not have the durability to be utilized in even light consumer usage just a few short years ago, but with new error correction innovations and NAND management techniques the viability of this type of NAND for consumers has become a reality.

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Simple rough math calculations can extrapolate that a write load of 10GB per day would result in a worst-case expected lifetime of 7 years for a 256GB TLC SSD. This number could easily be doubled for the 500GB SSD that we are testing today, and this is without even taking into consideration the ability of providing extra spare area to increase the endurance of the SSD. Users can also use the Samsung Magician SSD software to allocate more capacity of their SSD into spare area, commonly referred to as "over-provisioning," which results in increased endurance and write performance.

A lifespan of 7-14 years should be more than sufficient for all users whose workloads would allow the SSD to live that long. The SATA 1.0 interface was introduced in 2000, and SATA 2.0 followed in 2004, with SATA 3.0 making its debut it 2009. These point to a steady line of advancement in the storage technology, and soon another revision will be along. A lifespan of 7-14 years should carry a user well into another generation, or two, of storage devices.

Lower write speed is also one of the undesirable results from the complexity of programming TLC NAND, and this shows up the most in the lower capacity versions of these SSDs. The 500GB TLC model features higher write speeds of 330MB/s in sequential and 44,000 random IOPS.

This increase in write speeds and in endurance creates a compelling reason for users to select higher capacity TLC SSDs when making a buying decision. Today we give the 500GB TLC Samsung 840 a run through our performance tests to see just how well it stacks up to not only the smaller 250GB 840, but also offerings from the competition.