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I have an Acer aspire laptop with both Lubuntu 12 and Windows 7 installed on dual boot, my problem is when I boot into Lubuntu the screen is too dim and I barely can see the desktop icons while when I boot into Windows 7 the screen is normally lit and very bright.

I tried to adjust the brightness to a higher level using the Nvidia driver control center and also using randr command but it doesn't fix the problem, I checked the display driver (nvidia geforce 7) but it is correctly installed and configured.

One thing I should mention is when I connect to the laptop remotely using VNC viewer, the screen shown in VNC is very bright.

Can anyone please help?

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did you try adding kernel parameter acpi_backlight=vendor? –  Web-E Nov 20 '12 at 10:20
I opened /boot/grub/grub.cfg and added the line acpi_backlight=vendor then rebooted, but it didnt change anything, is this correct? –  Amjadov Nov 20 '12 at 12:55
I just tried the fn keyboard brightness shortcuts and they worked! thanks. –  Amjadov Nov 20 '12 at 13:32

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