First:
you should understand that encryption of data on a harddrive have nothing to do to get access to the harddrive.
The TPM hold only the keys for different security functions. TPM donīt do any encryption of data.
Second:
If a HDD have a security passwort, then a computer ask for it during boot. But this have still nothing to do with TPM or encryption.
Under Linux try at commandline:
"Even if you freeze or lock your drive by running the above command from a Lenovo laptop with a blank password, it is still possible to unfreeze and unlock it. First, plug the drive into a different computer. Second, perform a power cycle of the drive while you are booted into a drive utility (like Gparted). Third, issue the following command which should disable the security on the drive.
sudo hdparm --security-disable PWD
"
you can also try HIRENīs boot CD
Old Versions | Hiren's BootCD PE
and use : HDD Erase 4.0: Secure erase using a special feature built into most newer hard drives (Dos Freeware).
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