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 Samsung's 256GB SSD 850 Pro, 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 Plextor PX-256M6S, Toshiba Q Series Pro, Plextor PX-256M6M, Samsung SSD 840 EVO mSATA, OCZ Vector 150, OCZ Vertex 450, Silicon Power Slim S55, Samsung SSD 840 EVO, Seagate 600 SSD, SanDisk Extreme II, Plextor PX-256M5M, OCZ Vector, Plextor PX-256M5Pro Xtreme, Samsung SSD 840 Pro and Samsung SSD 840.
As I mentioned earlier, the 850 PRO is based on Samsung's MEX (S4LN045X01-8030) controller chip. Looking at the screenshot above, you can see that it performs equally well with both incompressible (0%) and compressible (100%) data.
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.
 Samsung SSD 850 PRO 256GB |
 Samsung SSD 850 PRO 256GB (RAPID Mode) |
 Samsung SSD 840 Evo 750GB |
 Samsung SSD 840 Pro 512GB |
According to Samsung, the 256GB 850 PRO is capable of reading at 550 MB/s and writing at 520 MB/s when connected to a SATA 6 Gb/s port. While the drive performed well, it came up a bit short of these numbers in CrystalDiskMark's sequential read and write speed tests. With RAPID mode enabled, these numbers increased considerably. Looking at the screenshot above, you can see that the 850 PRO was able to read at 4,515 MB/s and write at 3,316 MB/s.
HD Tach RW 3.0.4.0:
Next, I used HD Tach to test the 850 PRO's read, write and burst speeds as well as its seek times and CPU usage.
Samsung SSD 850 PRO 256GB
Samsung SSD 850 PRO 256GB (RAPID Mode)
Looking at the screenshot above, you can see that the 850 PRO had average read and write speeds of 443.3 MB/s and 407.8 MB/s respectively, as well as a burst speed of 392.0 MB/s. This time around, RAPID mode had very little effect on the drive's performance. Most likely, this is due to the way HD Tach bypasses the file system when performing its read and write tests.
ATTO Disk Benchmark 2.46:
I also used ATTO Disk Benchmark to test the 850 PRO'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.
 Samsung SSD 850 PRO 256GB |
 Samsung SSD 850 PRO 256GB (RAPID Mode) |
 Samsung SSD 840 Evo 750GB |
 Samsung SSD 840 Pro 512GB |
When tested with ATTO, the 850 PRO's read speeds topped out at about 564 MB/s and its write speeds at 536 MB/s. Here too, RAPID mode had very little impact on the drive's write speed. However, with it enabled, the 850 PRO was able to read at nearly 2,671 MB/s.
