Hi I own an Nvidia GTX 770 graphics card that is hooked up to my 4K monitor via display port (windows 8.1). Recently I played around with the colour settings on the nvidia control setting and set the digital Colour format to a colour that my monitor cannot display. Unfortunately the display at this point went blank, I waited for it to recover to the previous settings but unusually it didn't. I knew at that point that I would not be able to log into windows. I've tried many times to reset to windows but the graphics card reverts back to the new colour settings and the screen goes blank at log in. I've tried to revert windows settings to an earlier point, windows couldn't do it due to an error. And I;ve even tried in safe mode, but I cannot gain access to any of nvidia software. When in low resolution mode, as expected the nvidia graphics card applied the new colour settings outside the capability of the display. The only time I've managed to gain access into windows 8.1 is by swapping my display port for the HDMI port. So, my question is, how do I change the nvidia colour settings for the display port while the graphics card is connected to the HDMI cable???? This will resolve the colour display settings that I am currently having everytime I connect it to my display port. Please help
Hopefully someone has a better answer but I think you have to have your monitor connected via DisplayPort in order to be able to change anything and therefore the only solution that you haven't already tried would be hooking up a second display to the HDMI port and performing the changes on that.
I don't have nor can afford a second monitor with display port. Plus it could easily occur on the second monitor if it unable to display the colours that the settings has asked it to do. There must be a simpler idea. All I need to do is change the settings on the display port with HDMI connected.
You can try to reinstall GPU drivers in clean install mode. It should revert all settings to default values.
^ There's a better answer, that should work. I didn't mean get a second DipslayPort display, I meant leave your existing monitor connected to DP, connect any TV or HDMI monitor to the HDMI port, you should then be able to use the Nvidia control panel on the HDMI display to change the settings for the DP monitor.
I tried that with both HDMI and Display Port connected, and while my display port display was recognised, it did absolutely nothing when I changed the settings. It still reverted to the erratic colour settings. In the end I did what mbk1969 had suggested, and reinstalled my driver. It did the trick and now I know not to mess with colour YCbCr422, but 444 is okay.
