Up-to-date SSD manufacturers are inclined to employ MLC flash-memory with synchronous interface in their product lines. The implementation of exactly such memory interface allows balancing the advanced performance with moderate price. This is especially vital for SSDs with SATA 3 6Gb/sec interface. Nevertheless, some producers take the challenge to implement flash-memory with asynchronous interface in their drives. As a result, the final products go at more attractive price but with more modest speed characteristics. OCZ dared to overcome this speed drawback by releasing SSD Agility 4 series. The models included in the series are based on asynchronous flash-memory interface and, according to the company's words, prove to show quite decent speed index.
Despite the prevalence of SandForce controllers implemented in SSDs, OCZ decided to use quite different platform for its new series. Agility 4 employs Indilinx Everest 2 controllers which, in some way, follow technological approach of Marvell controllers. It should be stated that Indilinx Everest 2 does not utilize any data compression algorithms while processing. All the models use asynchronous MLC NAND memory type with ONFI 1.0 interface.
Agility 4 series has got a traditional to OCZ SSDs design; the top part of casing is made of soft plastic, while the bottom part – of metal alloy. All the models are delivered in a brand green color. Being an inexpensive SSD solution, Agility 4 cannot boast the availability of additional accessories in the nominal delivery set. This implies that the customer will have to buy the slide for the SSD installation into 3.5 inch PC bay. The implemented in the new series circuit boards are similar to those employed in Vertex 4 line, except for the memory type. Upon the whole, the series is represented by 4 models of various volume capacities: 64 GB, 128 GB, 256 GB, and 512 GB.
In addition, Toolbox applet, — OCZ brand utility, — allows the consumer to update the SSD firmware, monitor S.M.A.R.T. attributes, and complete Secure Erase activities without any problems or additional software.
Flash-Memory Characteristics (256 GB and 128 GB models)
1. Agility 4 256 GB. Flash-memory integrated in this model consists of 16 Micron chips with asynchronous interface ONFI 1.0. Each of the chips is equipped with two memory crystals developed according to the 25 nm technological process, and has got 128 Gbit capacity. Controller Everest 2 is able to use fourfold interlacing technique that is destined to enforce the speed performance.
2. Agility 4 128 GB. The most intriguing aspect pertained to this model is that its internal layout totally resembles the layout implemented in 256 GB item. Thus, it employs identical circuit board, controller and cache-memory type. The only distinctions are seen in the Micron chips capacity and interlacing type. The chips employed by this model have got 64 Gbits capacity and a single crystal. Everest 2 uses twofold interlacing in each channel.
The estimation of speed performance shown by Agility 4 models is realized with the help of CrystalDiskMark benchmark. Performance results demonstrate the imperceptible difference in writing and reading speed index. It should be underlined, that when the controller is provided with all necessary conditions for showing all its might, this SSDs are capable to achieve the performance results of products with synchronous memory type. However, when the operational speed is controversial to the interface bandwidth, controller is unable to gain the maximal results.
Thereby, the manufacturer claims the following consecutive writing and reading showings for different models:
— 64 GB model: consecutive writing speed – 200 mb/sec, consecutive reading speed – 300 Mb/sec;
— 128 GB model: consecutive writing speed – 300 mb/sec, consecutive reading speed – 420 Mb/sec;
— 256 GB model: consecutive writing speed – 410 mb/sec, consecutive reading speed – 420 Mb/sec;
— 512 GB model: consecutive writing speed – 410 mb/sec, consecutive reading speed – 420 Mb/sec;