Do you have a single drive or are you using a raid setup? If single, see below:
I would first attempt to update your drivers (chipset) from the manufacturers website. If you don't know the brand, open up your tower and look.
If updating the drivers does not solve the issue, see below.
I am assuming your drive(s) are not SSD based on the size. That being said, what RPM is the drive? If its older, it is most likely 4200, 5400. Try upgrading to 7200+ RPM drive, or SSD (This is extremely expensive).