The ATTO disk benchmark tests the drives read and write speeds using gradually larger size files. For these tests, the ATTO program was set to run from its smallest to largest value (.5KB to 8192KB) and the total length was set to 256MB. The test program then spits out an extrapolated performance figure in megabytes per second.Once again these results are very good and extremely impressive considering this drive costs under $100. To be perfectly candid it was not that long ago you would have had to spend 2-3 times more to get this level of performance!