Backlight gets darker instead of brighter or lighter Toshiba Satelllite P500
I have had two of these over-sized laptops develop what looks like a screen inverter fault. What happens is that as you increase the brightness setting, once you get past half way it gets darker instead of lighter, and may even shut off completely.
I thought it was a hardware problem, but a BIOS update from the Toshiba website seems to have fixed the problem. A Windows 7 update might have caused the problem. The affected machine was a pspg8a