A ‘measuring stick’ seems to have evolved in the SSD arena where performance can be separated by the type of data being tested. Some SSDs excel in transferring compressible data while others in incompressible data, such as we might see in music, video and photography.
Our report today will evaluate the new OCZ Agility 4 256GB SSD which houses the Indilinx ‘Everest 2’ platform, a platform that has been a true leader in incompressible data testing as seen in our Vertex 4 review this past April.
COMPRESSIBLE VS INCOMPRESSIBLE DATA
If I were to look back at the most common questions that I have addressed in the various forums, the top two are that of how an SSD can benefit the consumer and installation worries. The third is easily the question of compressible vs incompressible data and it usually comes in the form of “Why do my tests not match manufacturers specifications?” This is the bi-product, for the most part, of a SSD purchase where the manufacturer is using a LSI SandForce Flash Storage Processor (FSP) and not understanding that performance specifications have been arrived at through use of compressible of ‘o Fill’ data.
Understanding the difference between compressible and incompressible data then becomes key in the consumers SSD choice. Compressed data is representative of typical computer operating systems and applications, whereas incompressible data is representative of files such as photographs, videos and music. For the average user, either choice would be fine and one could not physically tell the difference between the two in typical system use, however, when it comes to incompressible data, things change just a bit.
For a gamer, the quick and almost instant loading of very complex scenes is vital in tournament play and especially with online competition. For a photographer, the ability to transfer tens of thousands of pictures a week quickly with a drive that does well with incompressible data saves time and increases productivity significantly. The same results can be drawn of those that create music and video’s in their daily duties as the swift transfer and manipulation of highly incompressible files is paramount.
OCZ AGILITY 4 256GB SATA 3 SSD
The exact scenarios are where OCZ hopes the Agility 4 might fall in and this SSD follows in the footsteps of the Vertex 4 that we reviewed previously. The Vertex 3 pulled in incompressible performance of 462MB/s high sequential transfer while, in the same benchmark, returned an incredible 105MB/s for low 4k random write performance which is key in the visible upgrade we see when moving from a hard drive to SSD. The difference between the two is that of value and the type of NAND flash memory being used. The Agility is the value oriented drive with the lesser performing asynchronous NAND flash memory while the Vertex 4 has the premium synchronous memory meant for enthusiasts. How would they fare with the Everest 2 platform though?
SYNCHRONOUS VS ASYNCHRONOUS MEMORY
OCZ has changed their provider of memory from Intel, as was the choice for the Vertex 4, to Micron which is being used in the Agility 4. Technically, there really was no change as both Intel and Micron work jointly together in there production of memory as part of IM (Intel Micron) Flash technologies which one could explore here.
As both manufacturers (and IMFT) produce synchronous and asynchronous NAND of almost identical exterior characteristics, there are really only two ways to identify the type ofmemory in use, these being through performance results or the NAND identification. For Micron, the difference is simply an ‘A’ to a ‘B’ in the identification name.
The memory on the left is the more affordable asynchronous type while that on the right is synchronous. The only change that is consistent in the identification is that of the last letter of the product code.