The upgrade procedure as below,
1. Installed AC adapter.
2. Please preparing a bootable utility disk and use it.
3. Decompress the ZIP file to this bootable disk.
4. Put the bootable disk into USB floppy, then boot
5. In DOS mode key in 'KBC' will start update.
6. After finishing, please restart the computer.
Here's other similar drivers that are different versions or releases for different operating systems: