The kernel driver for nvidia hardware will give you most, but not all, the functionality of your graphics card. It should give you better resolutions than you are getting. You can cycle through the available resolutions using the keyboard key combination ctrl + (the + key on the number keypad) and ctrl - to change screen resolutions.
To get the best performance from your nvidia card, you need to download and install the proprietary driver from nvidia, which you can get here.
The file has a .run extension. To install, you must make the file executable.
In a terminal, cd into the directory which contains the driver you downloaded. Run this command:
sudo chmod +x NVIDIA-Linux-x86_64-260.19.29.run (substitute the name of the driver you download).
Then install the driver with this command: ./NVIDIA-Linux-x86_64-260.19.29.run
When installation is complete, one of the files the nvidia package installs is /usr/bin/nvidia-xconfig. Do some research. I don't remember is the config app can be run from graphics mode, or if you have to switch to runlevel 1 or runlevel 3 (text mode) to run the config, then switch back to runlevel 5 (graphics mode).
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