There was a very in depth test done on this monitor for input lag and what not. The thing I found is that there is a setting for "OD" (overdrive) mode in your OSD. take no of what you have been at this whole time (off, on, or extreme). The test found that with OD "off" the response time average G2G was 10.3 ms which is much higher than the stated 4ms response. well Asus forgot to tell all the gamers that this needs to be on for it to be a 4ms response. the average response with OD "on" is 5.2ms G2G..but wait...Finally with it on "extreme" we get an average of exactly 4.0ms but it causes some extreme RTC overshoot of around 40%. If OD is set just to "On" there is only a 0.5% error and gets to 5ms response.
Already set on OD "Extreme" or "on"? well then if you are trying for that competitive rank or your eyes can't take the extra 3-4ms response time then go with the pg278q's 1ms G2G response. That should be about as good as it gets. There may be some other 1080p monitors out there that are a "Better" 1ms response than the pg278q's but its not 1440p. if you are going for competition in a specific game ask the guys that are at the top of the community for your game what they use. I am personally good with the 279q as I'm not trying to break any CS:GO records anytime soon. I'm mostly playing some gears of war or random steam games with my friends so I love the 279q due to the better colors it has and I'm not bothers by the response of 10ms (though I do notice it at times).
I7-4790k OC 4.9 1.375v
MSI Gaming X GTX 1080 OC core:2055Mhz Mem:5504Mhz
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