04-10-2011 10:48 PM
I was searching through the forums and found some threads on how to lower the brightness on my Z560. Everytime I use the FN + Up or Down arrows the brightness bar does not move.
I even tried going into Windows control pannel and the brightness sliders on there do not work at all. I tried reinstalling the Lenovo software as well and still no effect. The only thing I can do at this time is lower it through the Nvidia settings but that just darkens the screen. Any advice?
Solved! Go to Solution.
04-12-2011 02:25 AM - edited 04-12-2011 02:29 AM
04-28-2011 09:03 PM
Sorry about the delayed response, been busy the past month. I just recently reinstalled the operating system and the brightness controls worked.
However... after I updated the drivers from nvidias website they stopped working again. It even left the brightness at the setting I had it at before I updated. So I rolled back the driver and the controls work again. Is there any solution for this? Reinstalling the power management application does nothing and I dont want to use an outdated graphics driver simply for the brightness function.
04-29-2011 12:12 AM
05-05-2011 05:50 AM
I had this problem too on my Z560, and I found that the latest releases of the Nvidia driver do not seem to properly support brightness controls. I found that the last Nvidia release that properly supports brightness adjustment is 260.99.
08-28-2011 04:53 AM
Just updated my driver (after forgetting about the brightness issue from last time) and had it happen again.
So I decided to do a bit more digging into the issue. After a bit of googling I found the following thread on the NVIDIA forums:
Basically, there is a registry entry that NVIDIA sets that causes the problem. You can delete the registry key(s) and the Lenovo brigtness control will work (after a reboot).
The registry tree to search in is: HKEY_LOCAL_MACHINE\SYSTEM\
And search for keys called 'EnableBrightnessControl' (will have a value of 1).
When you find them, delete the specific key and search again (there may be more than one - eg: one per 'ControlSet'). When they're all gone, reboot your laptop. After the reboot it should all be working properly again.
PS: If there are any Lenovo people actually reading the forum, it may be worth incorporating this fix into the Lenovo Energy Management Driver installer.