For our today’s SSD test session we put together a system on an Intel H67 based mainboard. This chipset provides support for two SATA 6 Gbit/s ports, which we use to connect the tested SSDs.
We are going to benchmark two most popular Agility 4 models – SSDs with 128 GB and 256 GB capacity. We are going to compare them against their elder brothers featuring synchronous memory, Vertex 4 SSDs, as well as against several products with the same storage capacity based on controllers other than Indilinx Everest 2. SandForce products with 120 GB and 240 GB capacities are represented by typical SSDs with 25 nm synchronous ONFI memory (Corsair Force Series GT – analogue to OCZ Vertex 3) and typical SSDs with 25 nm asynchronous memory (Corsair Force Series 3 – analogue to OCZ Agility 3). Marvell 88S9174 controller will be represented by two Crucial m4 SSDs with 128 GB and 256 GB storage capacity built with 25 nm memory.
Overall our testbed was configured as follows:
- Intel Core i5-2400 (Sandy Bridge, 4 cores, 3.1 GHz, EIST and Turbo Boost turned off);
- Foxconn H67S mainboard (BIOS A41F1P03);
- 2 x 2 GB DDR3-1333 SDRAM DIMM 9-9-9-24-1T;
- Crucial m4 256 GB system disk (CT256M4SSD2);
- Tested SSDs:
- Corsair Force 3 Series 120 GB (CSSD-F120GB3-BK, firmware version 5.02);
- Corsair Force 3 Series 240 GB (CSSD-F240GB3-BK, firmware version 5.02);
- Corsair Force GT Series 120 GB (CSSD-F120GBGT-BK, firmware version 5.02);
- Corsair Force GT Series 240 GB (CSSD-F240GBGT-BK, firmware version 5.02);
- Corsair Performance Pro 256 GB (CSSD-P256GBP-BK, firmware version 1.0);
- Crucial m4 128 GB (CT128M4SSD2, firmware version 000F);
- Crucial m4 256 GB (CT256M4SSD2, firmware version 000F);
- OCZ Agility 4 128 GB (AGT4-25SAT3-128G, firmware version 1.5);
- OCZ Agility 4 256 GB (AGT4-25SAT3-256G, firmware version 1.5);
- OCZ Vertex 4 128 GB (VTX4-25SAT3-128G, firmware version 1.5);
- OCZ Vertex 4 256 GB (VTX4-25SAT3-256G, firmware version 1.5).
- Microsoft Windows 7 SP1 Ultimate x64
- Intel Chipset Driver 126.96.36.1999;
- Intel Graphics Media Accelerator Driver 188.8.131.5222;
- Intel Rapid Storage Technology 184.108.40.2066.
Random and Sequential Read/Write
We use CrystalDiskMark 3.0.1 benchmark to test the random- and sequential read and write speed. This benchmark is convenient to work with as it can measure the speed of an SSD with both incompressible random and fully compressible recurring data. This feature is important for testing SSDs based on SF-2281/2282 controller, which tries to compress the data before writing it into memory. So, there are two numbers in the diagrams below that reflect the maximum and minimum SSD speed. The real-life performance of an SSD is going to be in-between those two numbers depending on how effective the controller data compression is.
Note that the performance tests in this section refer to SSDs in their “Fresh Out-of-Box” state (FOB). No degradation could have taken place yet.
The Agility 4 series shows its special nature right away. We can see that it favors write operations, looking much better at writing than at reading. This is in fact the consequence of using the smart Everest 2 controller, backed up by a 512 MB cache, together with slow flash memory. When the controller is allowed to show its capabilities for memory access consolidation, the Agility 4 rises up to the level of SSDs with synchronous flash in performance. But the controller can’t save the day when the performance is limited by the flash memory interface.
As a result, the Agility 4 is comparable to the Vertex 4 at writing, which means that it is almost always ahead of competitors. But when it comes to reading, the Agility 4 falls behind. In typical usage scenarios with a lot of reads and a short request queue the Agility 4 is going to be no faster than SandForce-based SSDs with asynchronous flash. However, its performance does not depend on whether the data is compressible or not, so the new entry-level SSD from OCZ can be faster than its SandForce-based opponents working with random data. It is clear from the sequential read diagram.
Well, we should note that the sequential read speed of the Agility 4 may fluctuate, too. It is not the result of data compressibility but some other issue that has been brought about by firmware 1.5. We didn't see this effect with the earlier versions of OCZ's firmware.