AOC AG251FZ 240Hz FreeSync Monitor Review

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When 25” 240 Hz monitors first appeared costing over $500, we wondered if they would be a flash in the pan. The AOC AG251FZ is now the third such display to come to our lab, and after experiencing their superior gaming chops, we’re confident they will keep right on selling. Considering G-Sync’s price premium, it was only a matter of time before manufacturers included FreeSync users in their marketing strategy. When hardware performance is equalized, it’s nigh impossible to tell a difference between the two technologies. G-Sync offers more consistent specs from panel to panel, but if you choose carefully, AMD can deliver exactly the same experience.

We continue to be impressed with AOC’s efforts in the gaming arena. By developing the Agon line as a separate group of products, it’s put itself in competition with Asus ROG and Acer Predator, the two mainstays.

While it’s true that the AG251FZ represents a savings of $120 or so, you are giving up adaptive sync down to 24 Hz and blur-reduction in the process. At FHD resolution, the refresh rate issue just isn’t worthy of concern. When you spend $400-plus on a gaming monitor, it’s unlikely you plan to drive it with a slow PC. Even a modestly priced graphics board will push this display past 60 FPS. And proper selection of detail levels can get you over 100 FPS with little difficulty.

In our tests of G-Sync monitors, we’ve always found a brightness reduction associated with ULMB. Besides giving up adaptive-sync, the backlight strobe exacts an output penalty; though in fairness, that penalty is much smaller in more recently released displays. And it can be eliminated when the panel has sufficient output, like the AU Optronics 24.5” part in use here. Still, there will be purists who will insist that ULMB results in lower input lag. If that’s true, we’ve been unable to measure it. Our tests show the AG251FZ to be every bit as responsive as its G-Sync cousins.

Color performance is not a gamer’s highest priority, but our sample acquitted itself well in the benchmark tests. Most users will be satisfied with the AOC in its stock configuration. If you don’t calibrate, we suggest trying the Gamma 2 setting at the very least. Gamut and grayscale tracking are dialed in properly from the factory. And our press sample shows particularly good uniformity, superior to nearly every monitor we’ve ever tested.

If you’re still stuck on the AG251FZ’s FHD resolution and TN screen, we urge you to try one out before passing judgement. Those specs may seem anti-evolutionary on paper, but trust us, the gaming experience is more than a cut above the norm. Control response feels as though the system is reading your thoughts with every input resulting in instant action. The image becomes an extension of your hands.

For its top-shelf gaming performance and excellent out-of-box color, we’re giving the AOC AG251FZ our Tom’s Hardware Editor Recommended Award.

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Christian Eberle
Contributing Editor

Christian Eberle is a Contributing Editor for Tom's Hardware US. He's a veteran reviewer of A/V equipment, specializing in monitors. Christian began his obsession with tech when he built his first PC in 1991, a 286 running DOS 3.0 at a blazing 12MHz. In 2006, he undertook training from the Imaging Science Foundation in video calibration and testing and thus started a passion for precise imaging that persists to this day. He is also a professional musician with a degree from the New England Conservatory as a classical bassoonist which he used to good effect as a performer with the West Point Army Band from 1987 to 2013. He enjoys watching movies and listening to high-end audio in his custom-built home theater and can be seen riding trails near his home on a race-ready ICE VTX recumbent trike. Christian enjoys the endless summer in Florida where he lives with his wife and Chihuahua and plays with orchestras around the state.

  • apertotes
    Contrast 1000:1

  • darkomaledictus
    Won't be buying anything until that 4k, 144hz, hdr hits next year...
  • Newtoobuilding
    Would absolutely LOVE this for Quake live or Quake champions!!!!

    wonder if 1060 gtx would be anywhere close to supporting it
  • phobicsq
    I really don't see the point in 25 inches and 1080p.
  • alextheblue
    If you don't see the point in a display like this, you're obviously not in the target audience. I keep seeing comments on TN gaming display reviews that are absolutely ridiculous. This thing is about speed. Why are you reading a review of a 240hz TN gaming display? Go find reviews of different panel tech. That would be like commenting on a review of a professional IPS display, and pissing and moaning about the input lag and the low refresh rate. Do you also comment on reviews of sports cars and whine about the lack of third row seating and the low ground clearance? Simply incredible.

    Also, why is Tom's still using a 285 for their Freesync reviews? Even a 580 would help you put the display through it's paces a little bit more.
  • berezini
    LOL less product = Higher cost. Welcome to America.
  • mrmez
    20275445 said:
    Won't be buying anything until that 4k, 144hz, hdr hits next year...

    I'd like to know what graphics card would be running that.
    You know, since a 1080ti can barely crack 60fps @ 4k in GTAV.
  • Vishlod
    No CI / Common Interface? .. pass.
  • MaCk0y
    Can always use Custom Resolution Utility to increase the freesync range from 48Hz to a lower value. I have mine changed from 48 to 30. Not like it would be a good experience playing at that framerate though at least for an FPS.
  • AgentLozen
    I like the people who dismiss this monitor based on some superficial quality.

    "No CI / Common Interface? .. pass."
    "Contrast 1000:1 Next!"
    "Isn't a 10-bit AMVA panel? Skip."
    "It doesn't come in green? Try again."

    I like ALEXTHEBLUE's summary:
    If you don't see the point in a display like this, you're obviously not in the target audience...

    This Corvette doesn't seat seven passengers? I don't see the point to this car. Pass.