yes, when do anything, i remove the battery from mainboard, i very sure i write bios success, but it still not work...
Give this ago from M800 Manual
Recovering from a BIOS update failure
To recover from a BIOS update failure, do the following:
1. Remove any media from the drives and turn off all connected devices and the computer. Then,disconnect all power cords from electrical outlets and disconnect all cables that are connected to the computer.
2. Remove the computer cover. See Chapter 7 "Installing or replacing hardware" on page 51.
3. Locate the Clear CMOS /Recovery jumper on the system board. See "Hardware locations" on page 1.
4. Remove any parts and cables that impede your access to the Clear CMOS /Recovery jumper.
5. Move the jumper from the standard position (pin 1 and pin 2) to the maintenance position (pin 2 andpin 3).
6. Reinstall the parts and cables that were removed.
7. Reinstall the computer cover and reconnect any cables that were disconnected. See Chapter 7"Installing or replacing hardware" on page 51.
8. Turn on the computer and insert the BIOS update disc into the optical drive. Wait a few minutes. Therecovery process begins. After the recovery process is completed, your computer will shut downautomatically.Note: If the computer does not start up from the disc, select the disc as the startup device. See"Selecting a temporary startup device" on page 37.
9. Repeat step 1 through step 4.
10. Move the Clear CMOS /Recovery jumper back to the standard position (pin 1 and pin 2).
11. Repeat step 6 through step 7. Then, turn on your computer.