Model: Plextor S3C 256GB Solid State Drive
Manufacturer: Plextor
Provided By: Plextor LLC

As one of the biggest names in the storage industry, Plextor doesn't need much of an introduction. For nearly twenty years, they've produced some of the best optical drives the industry has seen. Known the world over for their quality, performance, and features, these drives have become favorites among consumers and professionals alike. Today, Plextor continues to lead the way by bringing cutting edge storage technologies to market. Along with an assortment of high-performance DVD and Blu-ray drives, the company offers a growing number of solid state drives.

At this year's Computex show, Plextor launched its new S3 series SSDs. Available in two form factors, the S3 series includes the M.2 2280 S3G and the company's latest 2.5-inch SSD, the S3C. These entry-level devices are powered SMI's SM2254 controller and are available with up to 512GB of SK Hynix's 14nm TLC NAND flash. To compensate for the slow write speeds typically associated with TLC NAND, the S3 series is equipped with Plextor's PlexNitro cache acceleration technology, which optimizes performance without taking up any space on the drive. The S3G and S3C also have many of the same features found on Plextor's higher end SSDs. In addition to the company's PlexTurbo intelligent RAM caching solution, the drives offer support for its PlexCompressor and PlexVault technologies.

The S3C is available in 128GB, 256GB and 512GB capacities. For this review, Plextor sent us the 256GB version of the drive, which is capable of delivering up to 550 MB/s sequential read and 510 MB/s sequential write speeds as well as up to 90,000 random read and 71,000 random write IOPS.

   Plextor S3C 256GB Solid State Drive
General Specifications
Part Number PX-256S3C
Capacity 256GB
NAND Flash SK Hynix 14nm TLC
Controller SMI SM2254
Cache 512MB DDR3
Form Factor 2.5-inch
Interface SATA III 6Gb/s

Sequential Read 550 MB/s Max
Sequential Write 510 MB/s Max
Random Read (IOPS 4K) 90,000 Max
Random Write (IOPS 4K) 71,000 Max

Environment and Reliability
DC Requirement 5V / 1.5A
Temperature (Operating) 0°C ~ 70°C / 32°F ~ 158°F
Shock 1500G (Max.), at 1 msec half-sine
Vibration (Operating) 7 ~ 800Hz, 3.08Grms
MTBF 1.5 million hours
Endurance (TBW) 70TB

Dimensions and Weight
Dimensions 100 mm x 69.85 mm x 6.8 mm
Weight 60g

Other Features
PlexTurbo, PlexCompressor, PlexVault and PlexNitro technologies
Supports latest LDPC technology to guarantee data integrity
Three year warranty

Needless to say, this is only a taste of what the S3C has to offer. To give you an idea of what to expect, we'll take a closer look at Plextor's new SSD and then see how well it performs. Does the S3C have what it takes? More importantly, is it the best bang for your buck? Keep reading as we find out.


The S3C comes in a simple, yet attractive, white box. In addition to the large "S3" series logo, the front advertises many of the drive's key features including its 256GB capacity, SATA 6Gbps interface, 3 year warranty and support for Plextor's PlexNitro, PlexTurbo, PlexCompressor and PlexVault technologies. The back of the box provides a bit more information regarding the S3C's features, specifications and box contents.

Plextor doesn't include a lot of extras with the S3C. Aside from the SSD, the only other thing in the box is a small, fold out guide containing warranty information as well as some brief installation instructions for both desktop and notebook computers in a number of different languages.

Physical Features:

Like Plextor's previous SSDs, the S3C is very well constructed. The drive's outer casing is made entirely out of metal. Along with it being strong and durable, it is very lightweight. On top of that, its brushed aluminum finish looks great.

The S3C is the first drive to use SMI's new SM2254 controller. According to various sources, the SM2254 is a custom version of the SM2258 that, for now, is specific to Plextor. The controller is powered by a 32-bit RISC CPU and offers support for 2D/3D MLC and TLC NAND flash from all the major NAND flash vendors. The SM2254 also employs SMI's proprietary NANDXtend error-correcting and data protection technology to triple the P/E cycles of TLC NAND. In addition, the controller features advanced Direct-to-TLC and SLC caching algorithms for optimal sustained read and write performance.

For the 256GB version of the S3C, Plextor has opted to use SK Hynix's 14nm TLC NAND flash. Looking at the pictures above, you can see that there are two 64GB NAND flash packages on either side of the PCB. The drive also has a single 512MB NANYA DDR3L memory chip that is used for caching.


Like Plextor's other SATA SSDs, the new S3C works with Plextor's Plextool software. Designed exclusively for Plextor drives, this free downloadable tool lets users check the status of their drive. From the main screen, users can view information like the overall health, total capacity, free space and firmware version of each drive.

The Secure Format feature gives users the option to delete all the data on an SSD in a way that it can never be recovered, restoring the drive to its original performance.

Plextool also gives users the ability to update a drive's firmware, perform a diagnostic scan and check its S.M.A.R.T. details and see if there are any issues.


The S3C also supports Plextor's PlexCompressor technology. Available as a free download, PlexCompressor is a smart compression program that compresses files left unused for an extended period of time in order to save space.

During each compression, only part of the space is compressed, avoiding occupation of system resources for long periods of time. After an extended period of use, most of the rarely used files are in a compressed state, and commonly used files are in a decompressed state. Compression of new files gradually decreases, until eventually almost no system resources are devoted to compression.

PlexCompressor can be monitored through its Viewer utility. From here, you can see which disks PlexCompressor is enabled on as well as the compression rate and the amount of increased free space.


Plextor's PlexVault software is aimed to provide a secure space where users can store personal information. Using the software, users can set up hidden disk spaces which can be opened or closed using a set of hotkeys. A password can also be set for even greater security.

When opened, the PlexVault volume will appear as an additional drive letter on your computer. Otherwise it remains hidden and cannot be found through the Device Manager or the Disk Administrator.


Last but not least, you have Plextor's PlexTurbo technology. This smart caching software uses system RAM to prolong the life of the drive and push its performance beyond the bandwidth limitations of the SATA interface.

Once installed, you can monitor PlexTurbo using the Viewer. This utility runs in the system tray, showing which disks Plextool is enabled on as well as the current cache capacity and the total reduced write volume. The reduced write volume is proportional to the extension of the drive's lifespan.

With the current version of PlexTurbo, you can set the maximum cache size and the cache release time. You can also have it preload data files that were used immediately prior to the last shutdown and automatically run the Viewer after start up.

By default, PlexTurbo uses anywhere from 1/4 to 1/2 of your system memory. With the M6 Pro and M6e, the maximum amount of memory it can use is 16GB. However, with the S3C, this number is capped at 1GB. Even with this limitation, we saw some considerable gains in our tests. When tested with CrystalDiskMark, ATTO and AS SSD, sequential read and write speeds increased, in some cases, by more than 13x.

Plextor S3C 256GB
Plextor S3C 256GB with PlexTurbo


Plextor S3C 256GB
Plextor S3C 256GB with PlexTurbo


Plextor S3C 256GB
Plextor S3C 256GB with PlexTurbo

The test system used in this review is equipped with an Intel Core i7-6700K CPU, GIGABYTE GA-Z170X-UD3 motherboard, 32GB (16GB x 2) of Crucial Ballistix Sport LT DDR4 memory, Samsung 960 PRO 512GB SSD and a GIGABYTE GeForce GTX 1060 WINDFORCE OC 6G graphics card. For the operating system, I installed a fresh copy of Windows 10 Enterprise.

To test the performance of Plextor's S3C SSD, I ran a series of benchmarks using CrystalDiskMark, HD Tach RW, ATTO Disk Benchmark, AS SSD, HD Tune Pro, Anvil's Storage Utilities, Iometer and PCMark 8. For comparison, I've also included test results from the Toshiba OCZ VX500, ADATA Ultimate SU800, Plextor S2C, Crucial M300, Plextor M7V, PNY CS1311, OCZ Trion 150, PNY CS2211, Plextor M6V, Crucial BX200, OCZ Trion 100, Kingston HyperX Savage, Crucial MX200, OCZ Vector 180, Kingston BX100, Samsung 850 EVO M.2, Samsung 850 EVO mSATA, AMD Radeon R7, Silicon Power Slim S80, Samsung SSD 850 EVO, OCZ ARC 100, SanDisk Ultra II, Crucial MX100, SanDisk Extreme Pro and Samsung SSD 850 PRO.

As I mentioned earlier, the S3C is based on SMI's SM2254 controller chip. Looking at the screenshot above, you can see that it performs equally well with both incompressible (0%) and compressible (100%) data.

CrystalDiskMark 5.1.2:

First, I ran a few quick tests using CrystalDiskMark. This benchmark tool measures the performance of a storage device by testing its sequential read and write speeds as well as its random read and write speeds using blocks 512K and 4K in size.

Plextor S3C 256GB
Plextor S2C 256GB

According to Plextor, the 256GB S3C is capable of reading at 550 MB/s and writing at 510 MB/s. Looking at the screenshot above, you can see that the drive had no problems reaching these speeds in CrystalDiskMark's sequential read and write tests.

Plextor S3C 256GB - All 0x00, 0Fill
Plextor S2C 256GB - All 0x00, 0Fill

The S3C performed equally well when using highly compressible 0x00 (0 Fill) data. This time around, the drive was able to read at 563.1 MB/s and write at 522.2 MB/s.

HD Tach RW

Next, I used HD Tach to test the S3C's read, write and burst speeds as well as its seek times and CPU usage.

Looking at the screenshot above, you can see that the S3C had average read and write speeds of 470.2 MB/s and 175.5 MB/s respectively, as well as a burst speed of 454.0 MB/s. The screenshot also shows that, like most other TLC-based SSDs, the S3C uses some sort of SLC caching. The drive starts writing at about 410 MB/s and then drops to about 175 MB/s when the write operation exceeds the size of the cache. The cache on the 256GB version of the S2C is also surprisingly small. It appeared to be about 4GB in size, which is about 1.5% of the drive's total capacity.

ATTO Disk Benchmark 2.46:

I also used ATTO Disk Benchmark to test the S3C's sequential read and write speeds. The tests are run using blocks ranging in size from 0.5KB to 8192KB and the total length set to 256MB.

Plextor S3C 256GB
Plextor S3C 256GB

When tested with ATTO, the S3C's read speeds topped out at about 563 MB/s and its write speeds at 511 MB/s.


AS SSD is a relatively new benchmark designed specifically for solid state drives. The application contains five synthetic tests used to determine the sequential and random read and write performance of a drive.

Plextor S3C 256GB
Plextor S2C 256GB

AS SSD also includes a copy benchmark. This test copies an ISO (two large files), program (many small files) and game (small and large files), returning the speed and duration of each.

Plextor S3C 256GB
Plextor S2C 256GB

HD Tune Pro 5.00:

Next, I ran a series of tests using HD Tune Pro. This hard disk utility measures a drive's performance by testing its sequential read and write speeds as well as its access time, burst rate and CPU usage. For this review, I'm also going to use it to benchmark the S3C's random read and write speeds, random access times and the number of operations per second.

Plextor S3C 256GB - Read Benchmark
Plextor S2C 256GB - Read Benchmark


Plextor S3C 256GB - Write Benchmark
Plextor S2C 256GB - Write Benchmark

The S3C performed relatively well when benchmarked with HD Tune. The drive had average read and write speeds of 517.2 MB/s and 173.9 MB/s, respectively, and a burst rate of 122.3 MB/s when reading.

Plextor S3C 256GB - Random Access Read
Plextor S2C 256GB - Random Access Read


Plextor S3C 256GB - Random Access Write
Plextor S2C 256GB - Random Access Write

When reading 4KB blocks, the S3C reached 24,922 IOPS and had an average speed of 97.352 MB/s. The drive was slightly faster when writing, reaching 24,981 IOPS with an average speed of 97.583 MB/s.

Anvil's Storage Utilities:

Anvil's Storage Utilities is another new benchmark designed with SSDs in mind. The standard storage benchmark measures a drive's performance by testing its transfer speeds, access times and IOPS.


Lastly, I ran a series of tests using Iometer. This tool can be configured to benchmark a number of things. In this case, I used it to measure the S3C's read and write speeds and the number of operations per second. The tests were run using random bytes and a queue depth of 3.

The S3C's performance was hit and miss when tested with Iometer. While the drive was able to read at a respectable 535.4 MB/s, its sequential write speed averaged out at only 183.92 MB/s.

The S3C wasn't one of the faster drives we've tested when it came to random reads and writes. In our tests, the drive was able to read at 102.34 MB/s and write at 169.34 MB/s.

According to Plextor, the 256GB version of the S3C is capable of 90,000 IOPS when reading and 71,000 IOPS when writing 4K blocks. In our tests, the drive reached 26,199 random read IOPS and 43,351 random write IOPS. Increasing the queue depth had little impact on the S3C's random write performance. However, with the queue depth set to 32, the drive was able to reach 76,488 random read IOPS.

Vantage PCMark 8 - Storage Test:

PCMark 8 is a complete benchmark for Windows. It includes five benchmark tests, each designed around a specific scenario. The storage benchmark measures drive performance using real-world traces recorded from Adobe Creative Suite, Microsoft Office and a selection of popular games.

PCMark 8 also includes a consistency test which measures the performance consistency and degradation tendency of a storage system. The test reports the performance level at the start, the degraded steady-state and the recovered state as well as the number of iterations required to reach the degraded state and the recovered state. For this test, we are focusing on the Adobe Photoshop (Heavy) trace and will look at both the bandwidth and latency of the drive

The S3C didn't do as well as some of the other drives in this test. Its bandwidth dropped below 60 MB/s during the degradation and steady phases, pushing its latency above the 600ms mark. The S3C's performance increased somewhat during the recovery phase. However, it still lagged behind most of the other drives, topping out at only 171 MB/s.

TRIM Performance:

While SSD's offer many benefits, there are some downsides to using flash memory. One of the biggest issues people run into is performance degradation. Over time, an SSD will run out of fresh blocks and will have to write over data the file system has marked as deleted. This procedure is very complicated and can slow an SSD's write speeds considerably.

To fix this problem, most manufacturers have added TRIM support to their SSDs. The TRIM command allows an operating system, such as Windows 7, to tell an SSD which data blocks are no longer in use. Using this information, the drive pro-actively erases these blocks and adds them to the free block pool.

To test the S3C's TRIM and garbage collection functions, I first put the drive in a "dirty" state. I used Iometer to fill 80% of the drive and then ran a random write test for 30 minutes. This had little impact on the S3C's read speed. However, its average writing speed dropped to a mere 56.89MB/s.

Plextor S3C - Dirty

To see how well the S3C could recover, I let the computer sit for about 30 minutes and then reran the test. The drive wasn't able to reach the factory fresh performance shown in our earlier tests. However, its average write speed climbed up to 271.72 MB/s.

Plextor S3C - After TRIM

Lastly, I used Parted Magic to perform a secure erase on the S3C. With the drive wiped clean, it had average read and write speeds of 528.48 MB/s and 481.56 MB/s, respectively.

Plextor S3C - Secure Erased

Final Thoughts:

As an entry-level SSD, it should come as no surprise that the Plextor S3C isn't the fastest drive on the market today. Nevertheless, with its advanced technologies and high quality components, the S3C is a great choice for the consumer looking for an easy and affordable way to improve the performance of their existing computer. Thanks to Plextor's PlexNitro technology, the S3C performed relatively well throughout most of our tests. In our sequential read and write tests, the 256GB version of the drive was able to read at speeds as high as 563 MB/s and write at speeds in excess of 524 MB/s. It also had no problems holding its own against other TLC-based SSDs in our random write tests, producing more than 43,000 IOPS at low queue depths.

I do need to point out that while Plextor's PlexNitro technology works well under normal conditions, it does have some limitations. If you have a heavy workload, where a consecutive write operation exceeds the size of the SLC cache, the S3C's write speed drops to non-accelerated levels. I also found this cache to be quite small. With the 256GB version of the S3C I was able to write a little more than 4GB worth of data before it filled. Given, this won't be an issue for the consumer looking to speed up boot or application load times, but, if you have heavier workloads, you may want to consider other options.

Fast read and write speeds aren't the only things the S3C has to offer. The drive is compatible with Plextor's Plextool software and supports their PlexTurbo smart cache technology. The S3C also works with the company's PlexVault and PlexCompressor software, which have traditionally been reserved for their higher end drives. That being said, the S3C does not support Device Sleep (DEVSLP) or hardware based encryption. This probably isn't an issue if you're looking for an SSD for your desktop computer. However, these are things you may want to keep in mind if the S3C is going in a laptop or if data security is a concern.

The 128GB version of the S3C is available now from retailers like SuperBiiz for around $71. For whatever reason, the 256GB and 512GB versions are not yet available, but, according to Plextor, they should be shipping within the next few weeks. No word yet on pricing but if they're like the 128GB version, they'll be reasonably priced.


  • Available in 128GB, 256GB and 512GB capacities
  • SMI SM2254 controller
  • SK Hynix 14nm TLC NAND flash
  • Good sequential read and write speeds under most conditions
  • PlexNitro technology optimizes performance without taking up SSD space
  • Supports PlexTurbo, PlexVault and PlexCompressor technologies
  • Direct-to-die write method for optimal sustained write performance
  • Large DRAM cache
  • Ultra-slim form factor
  • 3 year warranty
  • Affordably priced


  • Write speed drops when SLC cache is full
  • SLC cache is small
  • Does not support DEVSLP
  • Does not support hardware based encryption
  • Endurance rating is lower than S2C