Hey Simon,
To further extend on the topic of what i mean that there should not be an obvious bottleneck and that there will deffinitely be one, is indeed a very cryptic way to put it so let me reiterate.
By "Should not be an obvious bottleneck" i meant that OP will not notice anything at 1080p 144hz with that setup.
By "Bottlenecks being caused" i did not mean the exact scenario that applies to the OP. The bottleneck that you will have when running the 1080Ti + i5-6600@3.3Ghz will be noticeable when the user goes into video editing, animation, etc, where both GPU and CPU acceleration need to work in tandem.
On that note i further continued mentioning that Games do not use the CPU's 4-core structure completely and in the end, when playing, you will be using the 1st core at 70%+ and the second and third at around 30%, which is not that of a big deal when you have a high clock rate and around 4 cores.
On the other hand, when video editing, the software that you used is created to make use of all cores of the CPU almost equally, which is where you will actually notice the bottleneck of a the 1080Ti + the i5-6600.
To further reassure this, i suppose that you have at least seen or maybe read something about AMD's + Kronos's new Compute Graphics API: Vulkan, as well as Microsofts DirectX 12.
I will not go into detail to explain exactly how the API works, but in general, these API's will allow developers that are starting their new IP's to choose to use Vulkan or DirectX 12 to optimize their games, and if they do so and make their games work specifically with one of those two API's, you will see a very big shift of workload being taken off the CPU.
To explain a bit, when the GPU needs to call a texture or shader, etc., it calls a command to the CPU via API's. Vulkan and DirectX12 have.. lets say more "Flexible" API's, that will lower the strain on the CPU, and also allow for those games to have much better Multi Core performance when playing video games. (so we will not need such a high clockrate per/on a single core)
Cheers,
Jordan.