i installed xubuntu18 04 x64 bit and i installed xubuntu18 04 x64 bit and I cannot brighten or dim my display screen. the control panel and pop up widgets are there to use and they do slide back and forth but they do not change the brightness of the screen. Some where in the software it has been turned off or not installed. I have tried several fixes for many hours and so far it does not work and is killing my battery very fast since it is on high setting all the time. My laptop is a gateway nv59 (nv5927u) with typical intel i5 430m processor, intel graphics and nothing special about it, i have never opened the case or modified ithe hardware. all the hardware works perfect in windows OS, thus I know it should work. please help me i like xubuntu and i do not want to have to reinstall windows. thank you. the control panel and pop up widgets are there to use and they do slide back and forth but they do not change the brightness of the screen. Some where in the software it has been turned off or not installed. I have tried several fixes for many hours and so far it does not work and is killing my battery very fast since it is on high setting all the time. My laptop is a gateway nv59 (nv5927u) with typical intel i5 430m processor, intel graphics and nothing special about it, i have never opened the case or modified ithe hardware. all the hardware works perfect in windows OS, thus I know it should work. please help me i like xubuntu and i do not want to have to reinstall windows. thank you.
You can try to either enable brightness key handling in xfpm or disable it (let the Linux kernel handle it directly). In either case it seems your hardware isn't properly supported and there isn't much the power manager can do about that.