1. DOS mode:

Please follow the below steps to update BIOS:

Step 1: Please download Y4WS_115.zip file to desktop of Windows XP.
Step 2: Choose Y4WS_115.zip icon and use mouse right key to select "Extract All..." to decompress this file to a new diskette (disk2). 
Step 3: Create a bootable diskette (disk1).
Step 4: Insert the bootable disk1 into floppy drive (or external USB floppy drive) and power on the system. 
Step 5: Press <F2> to enter BIOS setup, choose [Boot] on the top menu, follow the instructions to select "Floppy Drive" as first boot device, then save setting and reboot. Please make sure to enable [Legacy USB Support] in Advanced page if you use external USB floppy drive.
Step 6: Insert the disk2 into floppy drive and execute the batch file bios.bat to update BIOS in DOS mode