Using a stopwatch, the playback is timed to the nearest tenth of a second. This forces Photoshop to constantly use the Scratch Disk as virtual memory. You define the Scratch Disk using Preferences in Photoshop. You have to quit and re-launch for the change to take effect. The ATTO disk benchmark was run using Express-Pro Tools 2.3.2 benchmark test with 8MB maximum file size and system disk cache disabled.
Sustained Rate is displayed in the charts.
Peak rates can be impressive but do not reflect typical drive performance.