Using some simple command you can check the performance of you hard disk, just execute following command…
# hdparm -tT /dev/hda
Timing cached reads: 732 MB in 2.00 seconds = 365.20 MB/sec
Timing buffered disk reads: 114 MB in 3.05 seconds = 37.38 MB/sec
Substitute /dev/hda with the name of your disk device.