GPU that wont bottleneck i5 7400 on csgo?

[y_r_amd_cpus_so_hot]

I'm running:
GTX 750 ti
i5-7400
8gb ddr4
SSD 128gb

I currently get ~170 fps in a 25 man deathmatch. Looking to get 300 constant or at least close to that (144hz). I get 350-400 fps in 5v5 competitive right now.
I play on 1024x768 black bars on all low settings apart from 4x MSAA.

I ran an fps benchmark ingame for 1024 and 1920

1920x1080 = Average framerate: 146.64

1024x768 = Average framerate: 163.75

(don't know what use this has, but when I did the 1920 test my GPU got a LOT louder, like server fan loud)

Not sure what I should be upgrading here, I would say my GPU, but considering the fps difference isn't that high its hard to tell.

I have 700 aud to upgrade

Thanks!

 

[hang-the-9]

You have quite a few options upgrading from a 750 Ti, with your budget, a GTX 1070 will be good and will last a long time for gaming. The game would be CPU limited also with very high FPS.