Hands-On FreeSync Testing
This article wouldn't be complete unless we had a hands-on section, would it? With Acer's help, I had the chance to do some real-world testing of the company's XG270HU, which I paired with a Gigabyte R9 290X (GV-R929XOC-4GD 4GB) slotted into an aging but still extremely capable Core i7-950-based system running Windows 7 x64 and AMD's Catalyst display driver version 15.20.1062.
Acer's XG270HU is the first FreeSync display I've used extensively. I've had an Asus ROG Swift PG278Q (G-Sync) on my desk for several months now, so my expectations were based on that screen as a benchmark.
My first impression was less about FreeSync and more about the display itself. Although it supposedly sports the same base characteristics (144Hz TN panel), the Acer looked to be better-built, with much better color and viewing angles than Asus' offering. Conversely, Asus' on-screen display is, at least to me, much easier to use. The LED that changes color to coincide with status on the Asus (white/normal, red/G-Sync, green/3D) was a nice touch that Acer lacks. All in all, though, ignoring FreeSync and G-Sync for a moment, the Acer felt like the display I'd keep if I were forced to choose one. And that's significant, considering that Asus' monitor currently retails for $670 compared to the Acer's $500 price tag.
Setting up FreeSync was even easier than I expected. When I installed the latest Catalyst drivers, a pop-up window informed me that both my GPU and display supported FreeSync, then guided me through the control panel's FreeSync setup. A minute or two later, I was ready to go.
I spent hours getting almost seasick spinning a boat around in the waters of The Witcher 3 and going through the older sights of Columbia in BioShock: Infinite, all the while getting a general feel for how smooth the whole experience was, and for telltale signs of stuttering or tearing.
The simple conclusion: FreeSync worked great. Within its stated range of 40 to 144Hz, and even pushing the GPU close to the lower end of that range, the experience was as consistent as I had gotten used to with G-Sync. It's just amazing to see that AMD managed to pull this off at almost $200 below the prices of comparable solutions from Nvidia.
However, there are a few shortcomings worth mentioning.
At the higher end of the range, when the GPU hits 144+ frames per second, G-Sync actually limits the whole pipeline to 144 FPS (similar, but not quite the same as enabling v-sync). By contrast, FreeSync does not. Frame rates actually go above 144 (about 160+). While AMD touts this as a "feature" of FreeSync, the byproduct is actually highly undesirable: screen tearing comes back when frame rates go higher than 145 FPS, even with FreeSync enabled. Personally, I prefer the frame-limited G-Sync implementation in practice. For most modern games and a majority of scenarios, it won't matter. Not many systems sustain 145+ FPS at 2160p. But as we saw from Borderlands in our testing event in LA, exceptions do exist.
[Update . . . This is a clarifying statement from AMD: "Users have the option to turn v-sync on, which will get rid of tearing once going above the DRR range of the monitor. To clarify, while in the DRR range of the monitor, FreeSync will always have the right of way before v-sync, which means v-sync will only turn active once outside the range." Filippo no longer has a FreeSync monitor, so we're unable to verify this first hand.]
Also, although the colors were definitely more vivid on the Acer than on Asus' screen, I did feel that the Acer suffered from more ghosting. As it turns out, the display unit that we were provided did not have the latest firmware, and consequently was disabling pixel transition overdrive with FreeSync enabled, resulting in the ghosting I experienced. If you buy this display for its FreeSync capabilities, do make sure to get the latest firmware installed.