OWC Mercury Electra 6G SATA 3 SSD 240GB Review – ATTO Disk Benchmark, Crystal Diskmark and AS SSD


ATTO Disk Benchmark is perhaps one of the oldest benchmarks going and is definitely the main staple for manufacturer performance specifications. ATTO uses RAW or compressible data and, for our benchmarks, we use a set length of 256mb and test both the read and write performance of various transfer sizes ranging from 0.5 to 8192kb.  Manufacturers prefer this method of testing as it deals with raw (compressible) data rather than random (includes incompressible data) which, although more realistic, results in lower performance results.

Our Test Bench brought out some great high sequential scores of 550MB/s read and 521MB/s write but something that we didn’t expect was the performance consistency shown as the sizes got larger.  With respect to the last four, its almost like we understand that the Electra has squeezed out every drop of juice that it could.  So far, the OWC Electra 6G appears to be one rock solid SSD!


Crystal Disk Benchmark is used to measure read and write performance through sampling of raw (0/1 Fill/compressible) or random data which is, for the most part, incompressible.  Many new SSD owners who can’t wait to test the performance of their SSD often grab this program and run a quick test, not realizing that they are testing with incompressible data rather than compressible data used in testing by manufacturers.  The following results will show RAW data (oFill) on the left with random on the right.

blankLots of information can be gained through this test.  One can see right off how asynchronous NAND flash memory doesn’t quite handle random (or incompressible) data the way that synchronous memory does.  The low sequential and 512K results on the right are new to most and the initial reaction of the masses in seeing new asynchronous memory equipped SSDs display such was not good.  As usual, the cream rises to the top though and we see that this drive posts excellent 4k low random write scores of 78MB/s.


Up until recently, ATTO was the only benchmark created specifically for SSD testing and it uses incompressible data.  AS SSD, for the most part, gives us the worst case scenario in SSD transfer speeds while using SandForce Driven SSDs as they use compression in storage as discussed earlier.  Many enthusiasts like to AS SSD for their needs.

blankblankAS SSD pretty much confirms that of Crystal (random data sample) and the difference we are seeing comes through the testing mechanism itself.  Crystal Diskmark provides the highest result reached through all tests whereas AS SSD provides the average.  The 4k result of 51931 IOPS is also a great showing.

Pg1 – Introduction

Pg2 – Interior Components and Test Protocol

Pg3 – ATTO, Crystal DiskMark and AS SSD Benchmarks

Pg4 – Anvil Storage Utilities Beta

Pg5 – HDTune Pro Testing

Pg6 – PCMark Vantage Comparisons and The Verdict!


Leave a Reply

Your email address will not be published. Required fields are marked *