The test system used in this review was an HP 8200 Elite. The computer came equipped with an Intel Core i5-2400 CPU, 4GB of DDR3 1333MHz memory, Seagate Barracuda 7200.12 ST3250312AS 250GB SATA 6 Gb/s hard drive, NVIDIA Quadro FX580 512MB PCIe graphics card and an Intel 82579-LM gigabit network card. For the operating system, I installed a fresh copy of Windows 7 Enterprise.

To test the performance of Silicon Power S55, I ran a series of benchmarks using CrystalDiskMark 3.0.1, HD Tach RW 3.0.4.0, ATTO Disk Benchmark 2.46, AS SSD, HD Tune Pro 4.61, Anvil's Storage Utilities and Iometer. For comparison, I've also included test results from the Samsung SSD 840 EVO, Seagate SSD 600, SanDisk Extreme II, OCZ Vector, Plextor PX-256M5Pro Xtreme, Samsung SSD 840 Pro, Samsung SSD 840, Kingston Ultra Plus, OCZ Vertex 4, OCZ Agility 4, Kingston SSDNow V300 and Kingston HyperX 3K.

As I mentioned earlier, the S55 is based on Phison's PS3108 controller. Looking at the screenshot above, you can see that it performs equally well when reading incompressible (0%) and compressible (100%) data. For whatever reason though, the write speed slowly decreases as the level of compression increases.

CrystalDiskMark 3.0.1:

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.


Silicon Power S55 240GB

SanDisk Ultra Plus SSD 256GB

According to Silicon Power, the 240GB S55 is capable of reading at 480MB/s and writing at 360MB/s when tested with CrystalDiskMark. As you can see, the drive had no problems exceeding these numbers when using random (default) test data.


Silicon Power S55 240GB - All 0x00, 0Fill

SanDisk Ultra Plus SSD 256GB - All 0x00, 0Fill

The Slim S55 performed even better when using highly compressible 0x00 (0 Fill) data. This time around, the drive was able to read at 512.0 MB/s and write at 472.1 MB/s.

HD Tach RW 3.0.4.0:

Next, I used HD Tach to test the S55'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 S55 had average read and write speeds of 438.3 MB/s and 327.3 MB/s respectively, as well as a burst speed of 349.4 MB/s.

ATTO Disk Benchmark 2.46:

I also used ATTO Disk Benchmark to test the S55'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.


Silicon Power S55 240GB

SanDisk Ultra Plus SSD 256GB

When tested with ATTO, the S55's read speeds topped out at about 556 MB/s and its write speeds at 510 MB/s.