I have lenovo 8807A46 desktop. The problem started when I was working with the computer but suddenly the main line AC (electricity) went down for couple of hours. When the electricity was back and turned on the computer there was no display or signal on the monitor even if i can hear a loud noise of fan in a desktop..
I read almost all the threads regarding the problem but still did not work for me.
I tried :
1) unplug the power cable and press the power button for 30 to 60 seconds and plug in the power cable and start the computer
2) since after removing the RAM and boot the computer there was no beep sound, thinking internal speaker cable might be unplugged, I tried removing dust from RAM method as well.
