The best Hard Disk Diagnostic alternative to SpeedFan is Argus Monitor. It's not free, so if you're looking for a free alternative, you could try DHE DriveInfo. If that doesn't suit you, our users have ranked more than 50 alternatives to SpeedFan and three of them are Hard Disk Diagnostic Tools so hopefully you can find a suitable replacement.
Monitoring temperatures and status of system components such as CPU, GPU and hard disk drive, fan speeds
i think it should be free
Supports more modern hardware, is still regularly updated.
DHE DriveInfoshows HDD information: Manufacturer, Product ID, Serialnumber, Firmware, ATA-Standard, BUS Info (S-ATA 150/300/600, P-ATA, USB, SCSI), Size, Buffer Size, Rotation Rate, Formfactor, Features, AAM, APM, Master Boot Record, Disk ID, Bootloader
Active@ Hard Disk Monitor is a disk utility that checks and monitors the status of your hard drives to help prevent data loss. The system is based on the Self-Monitoring Analysis and Reporting Technology (S.M.A.R.T.).
Germany
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Canada
Good alternative to SpeedFan. Far more up to date.