When using battery and system is running on the Intel GPU. The contrast is randomly changing.
Issue is solved by updating the Nvidia Optimus with Intel GPU driver.
Nvidia Optimus Driver for Windows 7 (32-bit)
Nvidia Optimus Driver for Windows 7 (64-bit)
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CHANGES IN THIS RELEASE
Versions 8.17.12.5738 (NVIDIA driver)
8.15.10.2253 (Intel driver)
[Problem fixes]
- Fixed an issue where the screen's contrast ratio might randomly change when
powered by the battery.
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