更新1:
When computer starts all three Caps,Num and Scroll light keep flashing continuously. Another working keyboard has also been tested but the result is the same.
更新2:
When computer starts all three Caps,Num and Scroll light keep flashing continuously. Another working keyboard has also been tested but the result is the same. Yes. That's what I have done. Buy a cheap USB keyboard and done. The keyboard was died and a high possibility the MOBO was partially died too. Thx a lot for the answers.