Why doesn't my laptop monitor turn on?

Monitor doesnt turn on with cpu

• When I turn on pc the monitor does not turn on, its main power on light is blinking the cpu starts running but somehow monitor fails to pick up. I have checked all connections and changed the power cable of monitor, besides my monitor can only be connected to power supply via cpu therefore it cant be connected directly to check with power issues. now the monitor has turned on, on its own while trying with other things and therefore now I am afraid to put off the main power supply to off, as it has happened before the monitor refused to start and so I keep the main power supply on that is to the stand by. I want to know how to rectify this problem, It seems to be the problem with the relay in monitor itself which just fails to crank up the monitor, can anybody guide me with any site which gives illustrated guide on how to open the monitor. any guidance regarding this is welcome, thanks.

• Answer:

  Your monitor may be in no signal mode, if you hear the beeps from your computer as if its working. Closely example the physical connectors, I've fixed alot of Dells where that is the number one culprit. The pins could be bent or the DVI(white) connector could be damaged or two pins could be going into 1. Another thing people dont know is breaking an USB port can cause your computer to not come on at all. So physically check all the parts you could have changed because usually monitors dont die and computers dont die instantly but humans can break something they can touch and not notice its broken.