Usually, you want both components to be used equally, at the desired frame rate you are shooting for, at less than 100%.
100% is not a good thing. If you are under your desired frame rate, and your components are at 100%, this means you may need to upgrade your components, or lower the graphical quality of your settings to achieve your desired frame rate. Furthermore, 100% utilized means maximum power draw (in watts) and maximum heat output.
I would check your monitor refresh rate and the settings you have in your game. You must have checked the usage due to some sort of stuttering or lag you noticed in game.
- Check to make sure you don't have too many programs starting with windows running as background processes. To check this press (CTRL + SHIFT + ESC) to bring up task manager and navigate to the "Startup" tab. Disable anything you don't use. Do not disable programs you don't recognize without doing a google search first!
- Lower your settings one step - Ultra to high for instance.
- Make sure you have V-Sync enabled if you do not have a G-Sync panel, or your panel is low ~60hz.
- You can overclock a 60hz panel (usually) to around 75hz. This will allow you to V-Sync to 75 FPS if you are hardware capable, giving a slightly smoother experience than 60 FPS. You can overclock your monitor by creating a custom resolution in the Nvidia Control Panel and setting the refresh rate to 75hz. If the screen goes dark, don't press anything, just wait until the timer runs out for the prompt and try lower refresh rates until one sticks.
To be clear: You cannot have a higher frame rate than the refresh rate of your monitor, those extra frames are dropped. (The only benefit I can think of would be lower input lag at the cost of visual fidelity.)