The OSD interface
The XL2420G actually has two OSD interfaces: one for the G-Sync scaler and another for Classic Mode. The screenshot below shows the G-Sync OSD, but you can use the buttons underneath to see the Classic Mode OSD.
The two interfaces look and behave a little differently, and they each expose a different set of features. This chart from BenQ's website breaks down some of the differences:
Notably missing from the G-Sync OSD are Display Mode, which lets the XL2420G simulate smaller display sizes through a clever application of black borders, and Smart Scaling, which gives the user control over how big simulated display sizes appear on the screen.
BenQ's Windows software is also out of bounds to the G-Sync mode. That software comprises Display Pilot and the Game Mode Loader.
Display Pilot is a substitute for the OSD with a number of extra features, such as desktop partitioning. The Game Mode Loader, meanwhile, allows third-party profiles to be downloaded and saved into the display's memory. The XL2420G has three custom profile slots, which can also be filled with custom settings defined through the OSD, the old fashioned-way.
Other Classic Mode exclusives include Instant Mode, which is supposed to cut input lag, and Smart Focus, which lets you zoom in on a portion of the screen, like a YouTube video. We didn't dwell on either those features—or the Windows software—since we were more interested in the G-Sync side of the XL2420G.
One OSD setting that's present in both G-Sync and Classic modes is AMA, or Advanced Motion Accelerator. BenQ says this feature raises the voltage applied to the panel's liquid crystals in order to improve gray-to-gray response times. The OSD presents three AMA settings: Off, High, and Premium. Here they are in action in Blur Busters' UFO Test:
Leaving AMA off clearly increases visible ghosting, so objects moving across the screen appear sort of smeared. The effect is somewhat subtle, though, and I honestly can't see much of a difference between the High and Premium settings. I wound up leaving the display on the High setting, the default, throughout testing.
Our testing methods
We've changed our testing methods up a bit since our last monitor review. Or, rather, I took some creative license to get around a small logistical problem.
The colorimeter on hand at TR's northern outpost is EyeOne's Display 2, whose bundled calibration software is close to a decade old and no longer supported. Rather than use deprecated software, I installed dispcalGUI, a calibration and characterization utility powered by the open-source Argyll Color Management System. dispcalGUI is a little more daunting and less user-friendly than consumer calibration software, but it's very powerful and quite a bit more feature-packed. Not only that, but it features more complete characterization functionality than HCFR, the tool we've used to test displays in the past.
So, I'd call this change a win-win.
Using dispcalGUI and our trusty colorimeter, I'll be comparing the XL2420G to my daily driver, the 24" HP ZR24W. The ZR24W retailed for around $400 when it came out roughly five years ago. Because it has an IPS panel and a 60Hz non-variable refresh rate, it's obviously in a very different league than the BenQ XL2420G. However, it should provide a helpful frame of reference on the image quality front. If the XL2420G can come close to the same level of color accuracy as an IPS monitor, then we'll know BenQ has a winner on its hands.
Luminance and contrast
We'll start by measuring black and white luminance at each display's minimum and maximum brightness settings. We can then compute contrast from those numbers. Note that we're testing the XL2420G in both G-Sync and Classic modes, and we're taking an additional set of readings at a normalized luminance setting of 120cd/m².
Thanks to its powerful LED backlight, the BenQ XL2420G runs circles around the CCFL-backlit HP monitor, be it in terms of peak brightness, contrast, or even black level.
Curiously, though, the BenQ monitor is measurably brighter—and has a measurably higher contrast ratio—in Classic Mode than it is with the G-Sync scaler enabled. The G-Sync mode isn't murky by any means, however, and 442 cd/m² seems almost blindingly bright to me in an indoor setting.