HDD Vendors

Vendor	Vendor-developed hard drive diagnostic software
Fujitsu	Web site: www.fujitsu.com (general), www.fcpa.com (hard drives) Drive diagnostics and firmware upgrade utilities are available at http://www.fcpa.com/support/hard-drives/software_utilities.html
Hitachi (and IBM)	Web site: www.hitachigst.com DFT (Drive Fitness Test) diagnostic utility is available at http://www.hitachigst.com/hdd/support/download.htm This tool works with IBM hard drives as well (since IBM sold its consumer hard drive development division to Hitachi).
Samsung	Web site: www.samsung.com Diagnostic tool Shdiag is available at http://www.samsung.com/Products/HardDiskDrive/utilities/shdiag.htm
Seagate	Web site: www.seagate.com SeaTools diagnostic software - http://www.seagate.com/support/seatools/
Western Digital	Web site: www.wdc.com Diagnostic and firmware updates are available at http://support.wdc.com/download/downloadxml.asp