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my laptop is lenovo g580. Configuration is CPU : Intel® Core™ i3-2370M CPU @ 2.40GHz × 4 GPU : Nvidia geforce 610M Kernel Linux 3.5.0-17-generic
My problem is that I cannot control the screen brightness. When I try to control the brightness using (Fn + up/down) the pop-up notification on the right top of the screen comes but the brightness does not change.
When I installed ubuntu for the first time the brightness control worked properly. But after the first reboot brightness not changing. Then I installed kernel 3.5. After that also the brightness control worked properly. But after the first reboot brightness not changing.
Now I observed that brightness control works well after the very first reboot of kernel update (update-initramfs -u).
What may be the reason? Thanks in advance.