The difference between the GTX and GTS is only 1C at high fan speeds. At low speeds, the performance is the same.
Push pull is not necessary needed but it's doesn't hurt to use it of course.
At 420 for a CPU will get you sweet temps, even at low speeds so you'll get a nice setup :-)
Corsair Vengeance LPX 3000C15
Samsung 970 EVO
Samsung 850 EVO
Dual Hardware Labs Nemesis 360GTS with FD Venturi HP-12 PWM fans
EK 1080 Strix waterblock + backplate
Fractal Design Define R6
Windows Pro 10
Acer XB271HU 1440p 165hz IPS
Steel Series QCK Heavy
Sennheiser HD598 + ModMic 4.0
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