Techiepedia are motherboard mfr and using J1900 for eDP with LVDS panel with PWM signal about control the brightness for VGA/eDP-LVDS displays under x86-platforms.
Our application or windows-default brightness control-bar option moves left/right but no changes for the light intensity.
Seems missing a design part related with PCH and your valuable feedback with guidelines are appreciated!
You may try using Intel Graphics control panel to adjust screen brightness
I recommend loading the latest video drivers for your graphics controller.
File name: GFX_Win7_8_8.1_10_64_220.127.116.1142.zip
File name: GFX_Win7_8_8.1_10_32_18.104.22.16842.zip
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