Besides fortnight what other games and at what resolution?

Based on the information you provided, yes, it sounds like your CPU is bottlenecking your GPU. You should be able to easily overclock the CPU by at least a few hundred MHz to help improve performance.

The thing is that my cpu doesn't run at 100%. Sometimes I see it under 80% while my fps goes 90. In majority, I'm hitting 144 fps but it go to 80-90 when they are a lot of things. Was pretty sure to have a bottleneck when I bought the 1060 but in my opinion it shouldnt be that much

Ability to use the CPU is highly dependent on the game and what ia going on in the game at any one time. Some operations are impossible to span more than 1 thread and some operations can span nearly an infinite number of threads. A game may max out your CPU at 25% CPU usage (single thread limited), 50% CPU usage (dual thread limited), 75% CPU usage (triple thread limited), or nearly 100% CPU usage (nearly perfect efficiency). If the game is only able to use 3 threads for the current operations/conditions, 80% CPU usage may be its max (3 threads @ 75% total usage plus 5% operating system usage).

It is behaving as if the CPU is bottlenecking the GPU. 100% CPU usage is not necessary before a bottleneck occurs. Whether or not the game is able to use all the CPU cores, making the cores faster will improve CPU performance.

welcome to trying to get high fps in games the higher you go in frame the more likely you will end up cpu bottle necked an i7 4790k may help alleviate some of your bottle neck but high fps is always hard on the cpu. if your motherboard supports doing a blck overclock and you know how to do them you might be able to overclock your i5 and see if it helps some

What I'm seeing is the 144htz setting being part of the issue....which is pushing the limits of the 1060. Either change htz setting so the card can handle it or get a better GPU.

Playing at 1080p will always leave CPU bound. This means you either have to OC your CPU as high as you can or lower some settings to help boost your FPS. Only playing at 1440p or higher are you GPU bound.

Hoggle
This is mostly true but would also depend on the settings being used in the game. Max settings can really push a graphics card even at 1080p since things like anti aliasing can render the picture 4X larger and then combine the super sampled image into the final 1080p frame to smooth out the picture. As said before the best way would be lowering every setting to the lowest available and seeing how the game plays and what the frame rate increase is. If it's the CPU the frame rate should stay the same while if it's GPU limited the reduction in what to process would make the game much faster.

Not true, maybe for 1 game or benchmark out there (like ashes of the singularity). For almost all games you are CPU limited. Check out the testing done by Hardware Unboxed (Techspot) below
 
Article 
Video Review
 
Gamers Nexus has also done reviews and shows that almost every game out there played at 1080p shows you are CPU limited.

mark_thaddeus
Not true, maybe for 1 game or benchmark out there (like ashes of the singularity). For almost all games you are CPU limited. Check out the testing done by Hardware Unboxed (Techspot) below
 
Article 

LOL that article is saying the exact opposite of what you are. 
 
"Overclocked, the 2600K averaged 140fps in Battlefield 1 and a GTX 1070 is good for around 115fps with the 8700K, so for the most part you should be okay. In Call of Duty WWII, the GTX 1070 offers 133fps on average with an 8700K while the overclocked 2600K managed 134fps with the 1080 Ti, so you're certainly on the edge with the 2600K and GTX 1070 combo."
 
They are literally saying a 7 year old CPU is not limiting with a 1070 in modern games (and OP only has a 1060). Not sure how you misunderstood so much.

ty_ger07
Regardless, I am quite sure that the OP's system is exhibiting a CPU bottleneck situation. The symptoms are very indicative. Also note that the 2600K is an i7 CPU which has higher performance in most applications compared to the OP's i5-4440 CPU. The 2600K may be old, but it is good. If they had to overclock a 2600K to prevent it from creating a measurable bottleneck paired with a GTX 1070, I think it is likely that the OP would need to overclock his 4440 to prevent it from creating a measurable bottleneck when paired with a GTX 1060.

I'm not as confident as you are I guess. It's on the edge in a lot of cases I think (which is indicative of a good CPU/GPU pairing IMHO).
For example, BF1, probably the best example of a modern game that is very demanding of both CPU and GPU and well optimized, pulls 122 FPS with an i5 6400 https://www.gamersnexus.net/game-bench/2673-battlefield-1-cpu-benchmark-dx11-vs-dx12-i5-i7-fx/page-2
The i5 6400 is ~ 5% faster than the i5 4440: http://cpu.userbenchmark.com/Compare/Intel-Core-i5-6400-vs-Intel-Core-i5-4440/3512vs1993
A 1060 puts down 95 FPS in BF1 1080p Ultra: https://www.gamersnexus.net/game-bench/2652-battlefield-1-graphics-card-benchmark-dx11-vs-dx12
 
So at least for BF1, OP would likely not be CPU limited. I'm sure there are examples either way, depending on settings and game. And I'm not suggesting no overclock (bring on the overclocks!) just that there could be something else going on (e.g. background process hitting the CPU causing FPS dips) and the easiest way to test is to drop resolution and settings in game to see what happens in a for sure CPU bound scenario.

somethingc00l
 
LOL that article is saying the exact opposite of what you are. 
 
"Overclocked, the 2600K averaged 140fps in Battlefield 1 and a GTX 1070 is good for around 115fps with the 8700K, so for the most part you should be okay. In Call of Duty WWII, the GTX 1070 offers 133fps on average with an 8700K while the overclocked 2600K managed 134fps with the 1080 Ti, so you're certainly on the edge with the 2600K and GTX 1070 combo."
 
They are literally saying a 7 year old CPU is not limiting with a 1070 in modern games (and OP only has a 1060). Not sure how you misunderstood so much.

So you don't get it either, if you look at ALL the CPU used with 1 card the 1080 Ti in all those graphs, you see minimums and average fps differ from best to worst meaning there is a CPU bottleneck at 1080p period. Compare that to the 1440p results and you see fps minimums and averages more or less be within 5% of each other means there is no CPU bottleneck (save for the really old and slow CPUs that can't push the GPU). Considering that he has an i5-4440 which is definitely weaker than an OC'd 2700k @4.8Ghz, he is being bottle-necked by his CPU. Now take into account the first post where the OP states that he is seeing 90-95% CPU usage and lower usage in his GPU means he is CPU limited.

somethingc00l

mark_thaddeus
So you don't get it either

Nah, I get it perfectly, it seems you are not paying any attention to the details here and have your mind made up already.
 

mark_thaddeus
1 card the 1080 Ti in all those graphs, you see minimums and average fps differ from best to worst meaning there is a CPU bottleneck at 1080p period. 

You say it yourself here, that's with a 1080ti. OP has a 1060. A 1080ti is well over double the speed of a 1060. The FPS in that chart with an overclocked 8700k is not over double the FPS of the non overclocked 2600k, so even a stock 2600k would not bottleneck a 1060 using the chart you like so much
 
If you are going to say a CPU is limiting a GPU, you have to be comparing the CPU to the actual GPU being used, not the top of the line GPU available.

The details you say? So when the OP says his CPU is showing 90~95% usage and the GPU usage is 50-70% what does that tell you? You can go to every tech site and they will tell you the same thing, at 1080p with his settings and with his setup he is being CPU limited.
 
You do know that a 1060 is as fast (more or less) as a GTX 980 right and I doubt that these cards are not enough or would be an issue or be a bottleneck playing at 1080p. Also the reason I showed you that particular graph is to show that CPU does make a big difference when gaming in 1080p and by using a 1080 Ti it eliminates any issue with the GPU being a bottleneck.
 
Heck even the link you gave the almighty Steve (GN) says - "For 1080p gaming with Ultra settings, .... The RX 480 (~$260) and GTX 1060 (~$265) are both more than capable of performing at 1080p, with the RX 480 a few frames ahead in Dx12, though with worse stutters, and the GTX 1060 ahead in Dx11. Both these ~$260 cards also scale well to 1440p and are fully capable of 1440p at Ultra settings, where we see framerates north of 60FPS for each vendor."
 
Doesn't that mean it's more than enough for playing at 1080p at least for BF1 and more than enough for Fortnight as the OP mentioned (he said he was getting 144 fps at low settings and doesn't want to play using low settings)?
 
Which brings me to my original point, his CPU is limiting his GTX 1060 when playing games at 1080p and he needs to upgrade it or at least OC it as high as he can to limit his CPU bottleneck.
 
Here's the almighty Steve testing the GTX 1060 - https://www.gamersnexus.net/hwreviews/2518-nvidia-gtx-1060-review-and-benchmark-vs-rx-480/page-5
 
If he's not getting fps close to those tests (since that test is using a CPU that won't bottleneck the GTX 1060) it means his CPU needs to be OC'd or upgraded.

EyeDeeNo
So putting aside CPU and GPU models also FPS it is more difficult to render at 1080 than 1.4 times of 1080 at 1440?

No. 1440p is more difficult to render than 1080p. Bottlenecking isn't specifically about difficulty. Bottlenecking is about balance and determining which component is slower than the other. At 1080p, it's easy for the CPU to be the limiting factor while the GPU is more than capable of higher performance but unable to achieve it due to lack of demand supplied to it.

EyeDeeNo
So putting aside CPU and GPU models also FPS it is more difficult to render at 1080 than 1.4 times of 1080 at 1440?

ty_ger07 is correct! Basically the higher the resolution of the content you render the more difficult it is to do so.

You're the first person to tell me that seeing a CPU usage at 90-95% and GPU at 50-70% (in most games) means nothing and I'll leave it at that.
 
You also said --- "If he gets 144 FPS with low settings and that FPS goes down when he raises the settings, that a GPU bottleneck for sure."
 
Of course when you raise settings the FPS for the game will lower, even if you use a 1080ti and you do the same thing and lower settings you would get higher FPS at 1080p. Vice versa, if I increase the settings (from low to ultra) using the 1080ti the FPS would decrease. So you're saying the 1080ti is GPU bottlenecking at 1080p because when you put all settings low in a game the FPS for the 1080ti is way high and when I put it in ultra settings the FPS are lower? Ok then...
 
You also mention the 2500k at 58 fps with WD2... that's at stock settings. What you didn't mention is when the 2500k is OC'd to 4.5 Ghz it hits 67 fps using the same GPU. That basically shows that the CPU is limiting the GPU performance, hence CPU limited/bottleneck. Consider that his chip is slower than the stock 2500k it means that he is CPU limited for that example you gave, because when he OC's it he will get more FPS just like the 2500k in the example you gave.
 
Also, the blanket statement I made is that for almost all games (notice I said almost all and not all) you are CPU limited at 1080p (specially when playing multi-player games).
 
I do keep learning and I do understand that the higher you go in resolution when gaming the less CPU bottleneck you will have. I've been building PCs since the Windows 3.1 and the reason I went 1440p is because CPUs most often than not will almost always bottleneck or limit your GPU performance at 1080p, unless you always buy the most expensive and fastest chips every year so it's able to push your GPU to the max, which isn't the most cost effective solution out there for most people.