This is the "secret" method Lenovo techs use in the field. It requires disassembling the laptop down to the bare motherboard, finding the J7 test point, and bridging two microscopic pads with a pair of tweezers at exactly the 4-second mark after pressing power.
Furthermore, on T470s with vPro (the i5-7300U or i7-7600U models), the AMT password is stored in the Management Engine's non-volatile memory. Clearing the BIOS does not clear AMT. You need a separate, nearly impossible to obtain, Intel engineering tool to reset that. The Lenovo T470 BIOS password is a fascinating piece of engineering. It is not "unbreakable," but it requires either a time machine (to use the old backdoor), a steady hand with a soldering iron, or a $50 donation to a Ukrainian firmware hacker on a Telegram channel. lenovo t470 bios password reset
Lenovo’s region is separate from the BIOS. If the previous owner enrolled the laptop in a corporate Computrace (Absolute Software) subscription, clearing the BIOS password won't kill the LoJack. Once the laptop touches the internet, it phones home to a geolocation server. This is the "secret" method Lenovo techs use in the field
For the hobbyist, the T470 is a challenge. It sits in a sweet spot where the hardware is cheap enough to risk bricking, but the architecture is modern enough to teach you about SPI flashing, differential Manchester encoding, and the quiet war between owners and manufacturers over who really controls the hardware. Clearing the BIOS does not clear AMT
If you try to brute force it, the system imposes exponentially increasing lockout timers. If you try to use a logic analyzer to sniff the SPI bus, you realize the data is encrypted with a key unique to the motherboard.
And if you see a T470 with a "Password not set" screen? That machine has a story. It has been freed.