Posted 20 June 2012 - 09:05 AM
The main concern of chkdsk is the condition of the file system, and it is a good idea to run it occasionally, or if there is any indication of file corruption. It checks the integrity of the system metafiles that keep track of all the files stored on the drive and attempts to correct any errors it may find in them. You can also use it to do a surface scan, in which case every drive cluster is read and the CRC checksum is confirmed. Any cluster which contains a sector that fails CRC will be marked out as bad. This can give a warning if a drive is developing faults, as bad sectors do not appear normally on modern drives until the internal maintenance system has run out of reserve repair sectors.
The drive manufacturer's diagnostic utility is mainly concerned with the electro-mechanical operation of the drive, and operates at a lower level than chkdsk, interacting with the drives own internal diagnostic and maintenance system, including S.M.A.R.T (Self-Monitoring, Analysis and Reporting Technology). However typically it can also perform tests like surface integrity scan, without regard to any file system present. Zero-fill is usually also available to wipe drives back to ex-factory state. This was sometimes erroneously called a Low Level Format in the past.
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