TESTS AND FACTUAL ANALISYS
http://www.blurbusters.com/gsync/preview2/
"subjective analisys" (the title of the page itself
The panel's 75Hz rate and decent response time meant there was
no visible ghosting either. If you're viewing content with a 16:9 or 16:10 aspect ratio, however, you'll end up with large, unused portions of the screen, like you see in the 4K Avengers clip above.
We also did quite a bit of gaming on the LG 34UM67, both with and without FreeSync enabled. We played some older titles like Left 4 Dead 2 (which can run at very high frame rates), and some newer titles like Crysis 3 and Metro Last Light.
When playing games that run at very high frame rates, the effects of FreeSync aren't quite as noticeable. We're sure if you stopped and stared and looked specifically for visual artifacts, you'd find some, but during actual gameplay they are not always
noticeable.
When playing more taxing games, however, with frame rates that may fluctuate above or below 60 FPS or so, the effect FreeSync has on the on-screen imagery and / or lag is great. Disabling V-Sync may eliminate lag, but tearing is evident. And enabling V-Sync may eliminate the tearing, but the lag can be annoying. With FreeSync, the on-screen images don't suffer from visual artifacts and the tearing is also gone.
We wish there was an easy way to visually convey how adaptive fresh technologies like FreeSync and G-Sync affects on-screen animation, but there isnt. We dont have a means to capture DisplayPort feeds and shooting video of the screen and hosting it on-line doesnt capture the full effect either. In lieu of an easy visual method to show how effective adaptive refresh rates can be, you'll just have to take our word for it.
We should also mention that simply using a higher refresh rate on your desktop is also great. There is a noticeable improvement when mousing or even moving windows around the screen, even at the LG 34UM67's 75Hz. If you're the type that gets headaches when looking at a 60Hz screen for too long, higher refresh rates may also help with that.
one review has stats and charts. the other has "feels". feel free to go with the second if you dont care about the actual science behind these two technologies.
a "good" review would be putting a freesync monitor next to a crt and film it on high speed camera. measure the input lag of a mouse factually and not limit yourself to "it feels fine". because in many applications
i would not be able to "feel" the lag which is, nevertheless, affecting me. just because its not "visible" it doesnt mean its not there.