MHDD is the most popular freeware program for low-level HDD diagnostics. MHDD supports these interfaces: IDE, Serial ATA, SCSI. Developed by Dmitry Postrigan
License: Free
MHDD is a free tool primarily focused on diagnosing and scanning hard drives for errors, while HDD Regenerator is a commercial software that offers advanced repair capabilities for bad sectors. MHDD is ideal for users looking for a portable solution, whereas HDD Regenerator is suitable for those needing more robust data recovery and repair options.