My Lenovo LOQ 15APH8 stopped starting properly. When I press the power button, the indicator lights up briefly and then the laptop shuts off. A repair shop had it for four or five days but could not fix it. It now reaches POST, but Windows boot loops with the stop code ACPI_BIOS_ERROR (0xA5). In the BIOS, the firmware version is listed as M3CN34WW, and it displays a Lenovo Legion logo even though this is supposed to be a LOQ. The correct BIOS version for my machine should be LYCN50WW. Linux Mint can boot from a USB drive, but Windows PE fails with the same ACPI error. How can I verify the hardware and safely restore the correct BIOS?
2 Answers
Do not force the normal LOQ BIOS updater to run while the system is identifying itself as M3CN34WW. Lenovo firmware packages usually check the platform ID, so the updater may refuse the file, and bypassing that check can permanently brick the laptop. The safest solution is to have Lenovo service or a qualified repair center reprogram the correct BIOS using the board's recovery or programmer procedure.
First verify that the machine and motherboard actually match the LOQ 15APH8 before attempting any BIOS update. From Linux, check the model, serial number, CPU, and other hardware details using tools such as dmidecode, lscpu, and lspci. A Legion logo and a completely different BIOS family suggest that the firmware may have been flashed with an image for another Lenovo model, or that the motherboard was replaced.
If the serial number or hardware does not match your records, contact the repair shop immediately. They may have returned the wrong machine or installed a different board.
The fact that Linux boots from USB does not prove the firmware is correct; Linux may simply be more tolerant than Windows of the ACPI tables. Save any important data while Linux still starts, then pursue a proper BIOS repair rather than repeatedly flashing different files.