Monitor flickers on and off when high refresh rate is selected on 2nd pc any ideas?

[newbie1337]

So I have a Acer Predator XB271HU On my main system specs as follows;

i7 8700k @5ghz
FE 1080ti
16gb ddr4 2133hz (low cl)

It works perfectly fine at any refresh rate and I use 165hz all day everyday.

My second pc that I use for lan events specs as follows;

i5 4690k @ stock
gigabtye 1070
8gb ddr3 @ 1600mhz

Won't work at anything higher than 85hz Using the same display port cable for both systems.
I've tried updating all the drivers and nothing seems to work been running my gpu under synthetics this afternoon to make sure It wasn't a gpu failure and its run perfect. Anyone any ideas?

 

[rgd1101]

MERGED QUESTION
Question from newbie1337 : "Monitor flickers on and off when high refresh rate is selected on 2nd pc any ideas?"

So I have a Acer Predator XB271HU On my main system specs as follows;

i7 8700k @5ghz
FE 1080ti
16gb ddr4 2133hz (low cl)

It works perfectly fine at any refresh rate and I use 165hz all day everyday.

My second pc that I use for lan events specs as follows;

i5 4690k @ stock
gigabtye 1070
8gb ddr3 @ 1600mhz

Won't work at anything higher than 85hz Using the same display port cable for both systems.
I've tried updating all the drivers and nothing seems to work been running my gpu under synthetics this afternoon to make sure It wasn't a gpu failure and its run perfect. Anyone any ideas?