Review – Samsung 840 And 840 Pro
Technology
Something that should be discussed, before we dive into the review is the technology used in this particular drive. The 840 is the first Samsung drive to utilize TLC NAND memory. TLC is short for Triple-Level Cell. As you can guess, this allows for more memory to be stored in the same amount of space as MLC. The specific difference is that TLC can store three bits per cell, where MLC is only able to store two. It also requires less power consumption than its predecessor.
The unfortunate downside, as you’ll see in the tests, and even the listed specs for the drive, is that transfer speeds tend to be lower than MLC. The more storage you stack on per chip means more time to transfer files. We’ll see just how much that impacts performance a little bit later.
One advantage that Samsung has over other TLC-based drives on the market is that they produce every component in-house. Naturally, that means that they are able to select only the best chips for their drives, while other manufacturers have to take what they can get.
Both the 840 and 840 Pro are using Samsung’s new 21nm flash, which is a big change from the 830, which still used the older 27mn technology. You’ll also find their new MDX controller, which as you saw in the technical specs, features greatly improved speeds.
Something else you may notice about the 840 in particular is that the capacity seems a little off. Rather than a 128, 256, or 512GB drive, like you normally see, this drive comes in 120, 150, and 500GB flavors. This wasn’t done to simply appeal to customers who are used to nice, round numbers for their hard drives. Samsung decided to build in a bit of overprovisioning. This leaves a little bit of dedicated space free, regardless of how much you put on the drive. It’s done to help maintain the integrity of the drive throughout its life. This likely has to do with the use of the new TLC NAND, as there have been concerns about TLC’s performance over time.
Test setup
We’ll be putting these drives through a variety of tests. The software we used is as follows:
- Anvil Storage Utilities 1.0.50 RC5
- AS SSD Benchmark 1.6.4
- ATTO Disk Benchmark 2.47
- CrystalDisk Mark 3.0.1
And here are the specs of the test rig we used for benchmarking:
For comparison, we’ve included benchmarks from the following two other drives we’re testing:
