Guild Wars 2

Not really. The game is mostly CPU bound, but its due to how the game is threaded that its inefficient, and bottle necks on the main thread. Because of this, you benefit more from per-core performance then multi-core performance…..

So in your case, you might want to upgrade the cooling of its not already running higher end heatsinks, and overclock the boost to 4 GHz- 4.1Ghz. The CPU can easily go up to 4.7Ghz, but it takes voltage fiddling and water cooling to do safely.

Alternatively you could turn down (or off) shadows and reflections, and lower the player model count/detail settings, as those have the most performance overhead in this engine.

Current generation CPUs are only 20-30% faster per thread than the CPU you have. To upgrade you would have to get a new motherboard as well as memory (DDR4), not an inexpensive option.

Just replacing CPU has most likely no effect at all. Your FPS is combination of many PC parts – CPU, GPU, Motherboard, Memory, HDD/SDD. Replacing them all would basically be building new PC, and then the eventual FPS depends mostly on how much money you want to spend.