If you own a Dell Inspiron notebook, you might be facing the LCD panel bightness issue when the system is running on battery power. Even though you have set the brightness to maximum in the operating system, the LCD panel seems to be not bright enough.
You might not have notice that there is a brightness setting in the BIOS.
1. Restart your computer.
2. Press F2 to enter the BIOS configuration menu.
3. Expand the Video tree menu on the left column and select Brightness from the sub-menu.
4. Move the bar to a higher value to increase the brightness. The default value is 3.
5. Save and exit the BIOS.
Now, your LCD panel should be brighter. However, the battery power will be drained much faster if the LCD panel brightness is increased.