- MHDD is the most popular freeware program for low-level HDD diagnostics. MHDD supports these interfaces: IDE, Serial ATA, SCSI. Also there is a possibility to access an USB storage, there are drivers for emulation (USB->SCSI).
- Free • Proprietary
Last version 4.6 was released in 2005. See http://hddguru.com/software/2005.10.02-MHDD/mhdd_changelog.en.html