Upgrading BIOS under DOS The following provides detailed steps on how to upgrade your BIOS (to AB19) under DOS using a bootable USB drive. Insert your USB drive into a host PC. Download the upgrade BIOS files from here and save them into your USB drive. Unplug the USB drive and insert it into your target system (COM Express Type 6 Raptor Lake-P). Make sure that your carrier board has all required accessories cables such as keyboard, mouse, and display connected. Upon startup, press [Del] on your keyboard when you see the ADLINK logo, as exemplified below, to enter BIOS. Select Boot section, and change Try Other Boot Device to Yes, as shown below. Save & exit BIOS. Re-enter BIOS > Boot, go to Boot Option #1 and set it as the USB drive containing the BIOS upgrade files, as exemplified below. Save & exit. Your system shall enter DOS mode. Find the BIOS directory Execute patching <pBIOS.nsh>. The system shall start to upgrade your BIOS. Once the upgrade is complete, remove the USB drive and restart your system. It shall enter BIOS directly. Check that your BIOS is of the correct version to finish.