Check that the CPU fan is running. This may be enough to cause the screen to come back on.


Many laptops have the ability to dim the light on the LCD by pressing a certain key, so make sure that the laptop is not just dimmed down.
 On some laptops, the screen will not be recognized automatically and you may have to press a certain set of keys on the laptop. You may need to consult your computer's manual for further instructions.
 A bad RAM could be the cause.;
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If you have two RAMs then remove both, and place back only one RAM.
Try them individually, then check the display.
 If you still have the same problem, remove the RAM from the slot. Clean it, and place it back in the same slot, or try another slot.
 Look for the VGA or the HDMI connector, connect it to the external monitor/TV then switch ON your laptop


If you failed to get the display on the external monitor, then use the proper combination keys ( Fn+F5 /the function key that has the monitor symbol on it) to toggle between your laptop screen and the external monitor.

If laptop is on but no display: If the external monitor works, this means the video card is just fine. Which leaves the screen, the motherboard connections, or the inverter.
 A laptop has a very tiny and long bulb which powers the screen, and when it burns out, the screen will go dark. Everything else is fine however, and it's only the bulb that needs replaced.
 If the bulb is burnt out, the computer should start up like normal including all of the lights, and the computer turning on. The only real difference is that the screen will be completely black and won't show any images.
 If you are able to make out a the background or at least see that there are some images, then you just have a burned out laptop LCD screen bulb.
 If you can't make out the background of the screen with a flashlight, chances are that the inverter is broken. What you want to do is hook up a monitor to the laptop, and if the monitor recognizes the laptop and the laptop's screen shows up, then you have a bad laptop inverter; that needs to be replaced. (You may also have a loose video cable, see below.)

, These are cheap to buy and swap, just figure out where it is on the motherboard.


If you have an inverter that doesn't give enough power: An inverter is simply a part in a computer which makes DC (Direct Current) into AC (alternating current), When the inverter in a laptop fails it doesn’t give the amount of power necessary for the screen and that’s why you may suddenly see it turn black for no apparent reason. Or when you turn on the computer the LCD screen doesn't turn on, even though everything else seems fine.
 Make sure that these are are not bent, cut, stripped, worn, or etc.
 There is a very thin cable which connects your laptop's motherboard to your screen and provides it with all the power and information needed to display the images. However, some laptops pull at the video cable upon opening, and may cause this cable to become loose. The only good way to tell is with the laptop open and the cable reset. However, it is recommended that this only be done by someone who has good knowledge and is comfortable with opening up the laptop. Otherwise, you'll need to ask a professional to check it.
, The video card controls all of the information that relates to images. Basically, it tells the screen what to display. If, after hooking up to an external monitor and the screen doesn't display, it is likely a video card that has the issue. (You may also see a black screen and hear random beeps.) The majority of laptop's video cards can't be replaced solely, and the entire motherboard may have to be replaced.
Make sure that the laptop's screen is on.
Test the automation features.
Check the RAM.
Remove the RAM.
Try changing the slot if it still does not work.
Try connecting an external monitor/TV to your laptop.
See whether there is a burned out LCD bulb.
Turn the laptop on.
Shine a flash light at the LCD while the computer is on.
Check to see whether the inverter is broken.
Test a new inverter.
Check the cables/connections.
Observe whether you have a loose graphics cable/video cable.
Note that if the cables are not an issue, the laptop may need a replacement motherboard (and see next).

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Check to see whether you have a bad graphics card/video card.
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