I faced the same issue even with the new driver too. However, I went to BIOS and disabled Hybrid graphics/Advance Optimus, and apparently, it solved the issue. I will now try the latest Studio Drivers and see if the issue is fixed there too. Because maybe it has something to do with the Hybrid Graphics Technology rather than NVIDIA Drivers.
So I have a G15 5515 Ryzen Edition with Windows 10. Been having this problem for like two months now and it's really getting on my nerves. I cannot change the brightness from 100% to anything else, be it the keyboard, settings or even Windows Mobility Center. Weirdly enough, when moving the slider to 0, the colors get oversaturated. I don't know if this is a hardware problem or it's just some software issue. I looked at this post where I then installed the latest NVIDIA driver, but this only fixed the oversaturation issue. [URL] Any help? Thanks in advance! Edit: I don't know if this is relevant but this happened after my laptop was connected for like 3 or 4 hours with an external monitor. I then unplugged the HDMI cable while it was still in extended display mode. Oh, and just now I uninstalled the monitor and restarted the laptop, which did nothing.
G15 5515, unable to change brightness