Access time is another important measurement. It measures the time the hard disk drive delays to start delivering data after the computer has asked a given data. It is measured in the order of milliseconds (ms, which is equal to 0.001 s) and the lower this value, the better.

The results presented by the two programs were slightly different, so this time we plotted a chart showing the two programs.

Western Digital RE4 and Caviar Black achieved exactly the same access time. According to HD Tune they achieved an access time 21% better than Barracuda LP and 32% better than Caviar Green. According to HD Tach they achieved an access time 19% better than Barracuda LP and 33% better than Caviar Green.