i absolutely follow the steps like unpluging the battery ,unpluging the ac/dc cable and pluging the ac/dc cable after holding keys [Fn]+[Esc] , alos, i unplug the HDD. But it still can`t boot from the usb floppy.
Also, during these process, i found some strange things:
1.when i held keys [Fn]+[Esc] and pluged the ac/dc , the motherboard came up with a very low beeps, long , clear and didn`t stop until i press the power button .
2.The usb floopy indicate light never lit up. But the cd-rom seem to work.
3.After i press the power button , whatever i still press the "Fn+Esc"Combo, the CPU FAN won`t stop until i press the power button for 5 seconds.Then the laptop restart instead of turning down which is what it is suppose to do.
In the end, i don`t kown whether there is a bios jumper on the motherboard .i need help and thanks in advance.