gtx 1070 with i5 4590

There is always a bottleneck in a computer. It cannot be avoided. Your CPU will hold back your GPU in some situations. Maybe 5 FPS or maybe 15 (game dependent). The more important thing to consider is:

1) Are you wasting money and getting a GPU that will perform the same on your CPU as a lower tier like a GTX 1060? Answer is no.
2) Would you stand to gain a greater benefit for the money by upgrading the CPU in addition to the GPU? Answer is no.
 

noca haki

Honorable
Dec 15, 2016
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10,535

tanks so i undrstand i will have lower bottleneck but is a not felling bottleneck ?
 


Depends on the game really. Currently, very few games will bottleneck significantly on that configuration.

I wouldn't bother with a CPU upgrade until something past Kaby Lake is on the horizon. Until then, you should be fine.