Your laptop works well before, but one day, when you turn your laptop on, the laptop works well while the laptop screen does not work as before.
The problem may be that the connection between the power cable and the screen isn’t well. You can reconnect it well to see whether the problem is solved or not.
When you want to know what the real problem it is, you should check that if your laptop screen is black like it’s blacked out or the laptop is completely black.
You can look at your laptop screen very closely and carefully, if you can see the words on the screen vaguely, this means that it is a dark screen, the problem may be backlight lamp is bad, what you need is replacing it with a new one.
If you can not see anything on the screen, the video card or the South Bridge is broken. The South Bridge is broken that may be because that your laptop runs a bit warmer for a long time. So you should take some measures to cool down the laptop in case that it happens again.
If the screen is completely black, you may also check whether your laptop screen is broken or not. You can test it with connecting an external monitor to your laptop, if the monitor can work well, that must be the problem of your laptop screen. If both laptop screen and external monitor can not work well, there may be a problem of the video card. While in many laptops, the video card can not be replaced from the motherboard. If the video card fails, you should replace the motherboard too.
If there is a poor contact of the CPU, it can also result in the same problem. You can take the CPU out carefully and then install it again.
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