I have a Cryo laptop with Windows 7 installed, bought in December 2011. Sometimes the screen seems to persistently dim and/or brighten up, even as I am doing things. In fact the brightness is varying even as I type this.

The battery is always fully charged and connected to the mains. I have checked many times the battery/power-saving settings always leaving the settings the same way; full brightness and never dimming when on the mains. Yet when the screen starts playing up I can end up with the screen dimming and brightening almost continuously.

I once went to the "adjust screen brightness" window when the screen had dimmed. I found the brightness slider on 100% (as I expected) but, as I dragged it to the left, to dim the screen, it first brightened and then started dimming, i.e. the screen setting said 100% brightness but it was only at, maybe 80%.

I have checked with Cryo and they just say check the power settings. I know what these are and how to work them and always set them to never dim/full brightness, yet still my laptop starts this dimming every so often.