HDTune

HDTune is a free, basic but useful maintenance tool. It can scan your hard drives and give you quite a bit of useful information about the state of the hardware and how well (or not) the operating system can access the data on them.

The basic HDTune app is free, but you can get an additional set of features for a small price if you purchase the "Pro" version.

The free version's window is divided into four main tabs: Benchmark, Info, Health, and Error Scan. The first tab runs a thorough scan of your hard drives by writing random data on it and reading it, while evaluating performance. The scan takes a few minutes and after it is done, you will see how fast your hard drive can read and write data from your hard drive, what the average access time is, and how much CPU is used during hard drive operations. These are all very useful pieces of information that you can use to diagnose most problems.

The info tab shows information about your hard drive. It displays the capacity, usage, type of file structure, and support for S.M.A.R.T. and other advanced features.

The Health tab shows S.M.A.R.T. info when available and the "Error Scan" tab is a simple logical scanner that can detect bad sectors.

All in all, the application provides some good data about your hardware state and for free. It is easy to use and it works extremely well.