For certain older or specific BIOS types, it can display the actual plain-text password or generate a master backdoor password.
Turn off the target computer completely. Insert the prepared USB drive. Power the system back on and immediately begin tapping the manufacturer’s designated . Common boot menu keys include: F12: Dell, Lenovo, Acer, Gigabyte, Toshiba F11: MSI, AsRock F9: HP F8: ASUS Esc: Samsung, Sony Step 2: Select the USB Drive
Power on the system. Because the CMOS registers were intentionally corrupted and cleared, the motherboard will likely pause during POST (Power-On Self-Test) and flash a warning message on the screen, such as: “CMOS Checksum Error - Defaults Loaded” “Press F1 to Run Setup, Press F2 to Continue”
Once completed, you have a bootable PC CMOS Cleaner USB. How to Use PC CMOS Cleaner 2.0 USB Boot pc cmos cleaner 2.0 usb boot
: Resetting the CMOS will revert all BIOS settings—such as boot order, overclocking profiles, and system time—to factory defaults. Legacy Tool
is an industry-standard, bootable utility designed to bypass, recover, or completely wipe BIOS passwords and reset the motherboard's Complementary Metal-Oxide-Semiconductor (CMOS) data back to factory defaults.
: Typically used by creating a bootable USB or CD, allowing it to run independently of the installed operating system. HP Support Community How to Create and Use a Bootable USB For certain older or specific BIOS types, it
| Problem | Solution | |---------|----------| | Computer does not boot from the USB drive | Ensure the USB drive is set as the first boot device in the BIOS. If the BIOS is password-locked, try pressing the boot menu key (F12, ESC, etc.) immediately after power-on, which often bypasses the BIOS setup password. | | PC CMOS Cleaner does not find the password | This is common on modern systems. Try selecting option to reset the entire CMOS rather than displaying the password. If that fails, the tool cannot help with your hardware. | | The standalone ISO method fails to boot | Use the advanced Parted Magic method described above, which has a much higher success rate. | | Rufus warns about ISOHybrid image | This is normal. Choose the "Write in DD Image mode" option if prompted for best compatibility. | | The system freezes during boot | Some older hardware may struggle with the Linux kernel of Parted Magic. Try using an older version of Parted Magic (version 5.7 is commonly referenced) or use the standard ISO method with a different USB port (preferably USB 2.0). |
Because PC CMOS Cleaner 2.0 is distributed as an .iso file, copying and pasting the file directly onto a USB drive will not work. The drive must be provisioned with a Master Boot Record (MBR) or GUID Partition Table (GPT) and a bootloader.
While PC CMOS Cleaner 2.0 is highly effective for legacy systems, hardware architecture has shifted significantly over the last decade. Modern UEFI Restrictions Power the system back on and immediately begin
Select the ISO in your bootable tool, target the USB drive, and start the flashing process. Steps to Boot and Use the Tool
The standard image file of the software.
| Method | Speed | Difficulty | Success Rate (2020+ PCs) | |--------|-------|------------|----------------------------| | CMOS Battery Pull | 15 min | Easy | 30% (Passwords remain) | | Jumper Short | 2 min | Medium | 60% | | | 1 min | Easy | 75% | | MS-DOS DEBUG script | 2 min | Expert | 40% (Old systems only) | | SPI Flash Programmer | 20 min | Hard | 98% |
The tool will load (usually from a specialized Linux environment like Parchon Magic).