Bottleneck with i5 6600k and a gigabyte gtx 1060 with 8 gb ram ?

[Spriterfight]

I dont understand when i play on gta v or just cause 3 i got in a
fluctuate fps around 50-90 fps. I dont understand why.I dont want buy new pparts dor my computer so i wrote my problem here. and the resolution is 1680x1050.I always play on high graphic but on high i got 50-60 fps sometimes 80.

 

[COLGeek]

MERGED QUESTION
Question from Spriterfight : "Bottleneck with i5 6600k and a gigabyte gtx 1060 with 8 gb ram ????!!!!!!!!"

I dont understand when i play on gta v or just cause 3 i got in a
fluctuate fps around 50-90 fps. I dont understand why.I dont want buy new pparts dor my computer so i wrote my problem here. and the resolution is 1680x1050.I always play on high graphic but on high i got 50-60 fps sometimes 80.

 

[justanenenthusiast]

No, it should not. Be sure to check temps on CPU and GPU, but it sounds to me like your
1. GPU vRAM is full
or
2. RAM is full

It is always possible that your CPU or GPU is being throttled due to heat.
I would suggest MSI Afterburner to monitor temps, or Hwinfo64.