I didn't use the calibration and testing tools at first, since most end-users will not have any of 'em available. I took the monitor out of the box, and prepped the tests on it uncalibrated. Then, I went on and took a few calibrated tests as well.
Now, unlike the PB287Q, I didn't prepare the same AMD and NVidia system line-up. Instead, I only hooked PG278Q up to a machine using an NVidia G5X780Ti. There was no issue installing it, since all I had to do was plug it in. The first thing I did was load-up the driver and check the G-Sync tab. It was enabled by default, and the red-ring around the base was indicating it.
I tested the screen using NVidia's 340.3 BETA driver.
Now, I was interested in stuttering or screen tearing, if of that was visible at higher than 60Hz refresh rates. So, I loaded up my Steam collection (and then Origin), and prepared a number of games.
Metro: Last Light
Witcher 2: Assassins of Kings
Even with GTX780Ti, getting 100+ frames-per-second consistently at a 2560x1440 resolution is a daunting task. Often, we registered some wild frame-rate oscilation. This was actually in our favour, because sinking from 130frames to 55 would cause tearing and stuttering on most, and that's exactly what G-Sync is supposed to remedy.
Whilst my monitor testing experience is limited, I took the i1 Display Pro, with X-Rite i1 Pro, and used 'em alongside SpectraCal's CalMan 5.201 software package, for some added results regarding the image quality
PG278Q also comes with ASUS GamePlus feature, which adds a crosshair in the center of the screen, or insert a count-down timer, for use in realtime strategy games.
However, both options cannot be enabled simultaneously. There are four available crosshair designs to choose from, and the timer can be placed on the bottom, middle or top of the screen, and set for a limited duration of 30, 40, 50, 60, or 90 minutes.
ASUS Light In Motion
The monitor has a patterned ring around the base, which glistens in a bright red color. This is part of ASUS' Light-in-motion feature, and is turned on when G-Sync is active. Of course, you can also turn-it off in the OSD, but it takes away some of the that visual flair the screen comes with.