As many of the answers here already mention, you are unfortunate. The Lenovo G470 seems to have a HSM (Hardware Security Module) of some sort that stores the password hash for your BIOS. It is not stored in Non-volatile either, so using reset pads or jumpers will not work. This is to prevent unauthorized access, and while it in theory can be done, it requires time, equipment and skills not worth the age of the laptop. Your best option is a replacement Motherboard on ebay.
Discussion on question by Chemist: Re…
Discussion on question by Chemist: Re…