Depends on the game - some will hit 144fps or much more with a lesser processor. Some won't do it with the most expensive CPU you can buy. If you have particular games in mind, research benchmarks for those with your CPU/GPU combo or something close.
Try this test:
Run YOUR games, but lower your resolution and eye candy.
If your FPS increases, it indicates that your cpu is strong enough to drive a better graphics configuration.
If your FPS stays the same, you are likely more cpu limited.