How to dim screen of my laptop when holding Fn key with brightness key is not working

Generally, we'd like to adjust the brightness of the computer screen to help adapt different situation. But we may find out sometimes that we cannot dim screen of our laptop when holding Fn key and the brightness key isn’t work. And the icon of the power in the right corner disappears. 

This may be caused by the inefficiency of the graphics driver on your laptop, so you need to update or re-install it manually or through a driver tool.

To solve this problem effectively, we can try the following solutions.

Solution one:

1 Check your graphics card version in Device Manager, Win+R, input: devmgmt.msc;

2 Go to the official website of the graphics card vendor and find out a proper one;

3 Restart your PC and check if it works.

Solution two:

Use Driver Booster , a great driver manage tool which helps to update and backup your drivers easily. Common driver problems such as blue screen of death, network problems, no sound problems etc can be properly repaired with Driver Booster. So according to the description above, we can just update the graphics driver with Driver Booster.

1 Download and install Driver Booster;

2 Run it, and the program will start scanning automatically;

3 After the scan, there will be a list of outdated drivers, you can update them all or the one you need;

4 Restart your PC to check if the problem has been repaired.