FreeSync Features

In many ways FreeSync and G-SYNC are comparable. Both refresh the display as soon as a new frame is available, at least within their normal range of refresh rates. There are differences in how this is accomplished, however.

G-SYNC uses a proprietary module that replaces the normal scaler hardware in a display. Besides cost factors, this means that any company looking to make a G-SYNC display has to buy that module from NVIDIA. Of course the reason NVIDIA went with a proprietary module was because adaptive sync didn’t exist when they started working on G-SYNC, so they had to create their own protocol. Basically, the G-SYNC module controls all the regular core features of the display like the OSD, but it’s not as full featured as a “normal” scaler.

In contrast, as part of the DisplayPort 1.2a standard, Adaptive Sync (which is what AMD uses to enable FreeSync) will likely become part of many future displays. The major scaler companies (Realtek, Novatek, and MStar) have all announced support for Adaptive Sync, and it appears most of the changes required to support the standard could be accomplished via firmware updates. That means even if a display vendor doesn’t have a vested interest in making a FreeSync branded display, we could see future displays that still work with FreeSync.

Having FreeSync integrated into most scalers has other benefits as well. All the normal OSD controls are available, and the displays can support multiple inputs – though FreeSync of course requires the use of DisplayPort as Adaptive Sync doesn’t work with DVI, HDMI, or VGA (DSUB). AMD mentions in one of their slides that G-SYNC also lacks support for audio input over DisplayPort, and there’s mention of color processing as well, though this is somewhat misleading. NVIDIA's G-SYNC module supports color LUTs (Look Up Tables), but they don't support multiple color options like the "Warm, Cool, Movie, User, etc." modes that many displays have; NVIDIA states that the focus is on properly producing sRGB content, and so far the G-SYNC displays we've looked at have done quite well in this regard. We’ll look at the “Performance Penalty” aspect as well on the next page.

One other feature that differentiates FreeSync from G-SYNC is how things are handled when the frame rate is outside of the dynamic refresh range. With G-SYNC enabled, the system will behave as though VSYNC is enabled when frame rates are either above or below the dynamic range; NVIDIA's goal was to have no tearing, ever. That means if you drop below 30FPS, you can get the stutter associated with VSYNC while going above 60Hz/144Hz (depending on the display) is not possible – the frame rate is capped. Admittedly, neither situation is a huge problem, but AMD provides an alternative with FreeSync.

Instead of always behaving as though VSYNC is on, FreeSync can revert to either VSYNC off or VSYNC on behavior if your frame rates are too high/low. With VSYNC off, you could still get image tearing but at higher frame rates there would be a reduction in input latency. Again, this isn't necessarily a big flaw with G-SYNC – and I’d assume NVIDIA could probably rework the drivers to change the behavior if needed – but having choice is never a bad thing.

There’s another aspect to consider with FreeSync that might be interesting: as an open standard, it could potentially find its way into notebooks sooner than G-SYNC. We have yet to see any shipping G-SYNC enabled laptops, and it’s unlikely most notebooks manufacturers would be willing to pay $200 or even $100 extra to get a G-SYNC module into a notebook, and there's the question of power requirements. Then again, earlier this year there was an inadvertent leak of some alpha drivers that allowed G-SYNC to function on the ASUS G751j notebook without a G-SYNC module, so it’s clear NVIDIA is investigating other options.

While NVIDIA may do G-SYNC without a module for notebooks, there are still other questions. With many notebooks using a form of dynamic switchable graphics (Optimus and Enduro), support for Adaptive Sync by the Intel processor graphics could certainly help. NVIDIA might work with Intel to make G-SYNC work (though it’s worth pointing out that the ASUS G751 doesn’t support Optimus so it’s not a problem with that notebook), and AMD might be able to convince Intel to adopt DP Adaptive Sync, but to date neither has happened. There’s no clear direction yet but there’s definitely a market for adaptive refresh in laptops, as many are unable to reach 60+ FPS at high quality settings.

FreeSync Displays and Pricing FreeSync vs. G-SYNC Performance
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  • Flunk - Friday, March 20, 2015 - link

    Free Sync = Adaptive Sync + AMD GPU + AMD Drivers. Reply
  • Gigaplex - Thursday, March 19, 2015 - link

    Adaptive Sync as part of the DP spec is optional. It's not required for certification. Reply
  • JonnyDough - Monday, March 23, 2015 - link

    Yep. Reply
  • FriendlyUser - Thursday, March 19, 2015 - link

    Read the article. Freesync monitors are less expensive. Plus, they have a much better chance of getting Intel support or even Nvidia support (wanna bet it's going to happen? they're simply going to call it DisplayPort variable refresh or something like that...) Reply
  • imaheadcase - Thursday, March 19, 2015 - link

    Intel support? I doubt you will find anyone buying these with a intel GPU. Why would nvidia support it with its investment already in Gsync..with new Gsync monitors IPS shipping this month? Makes no sense. Reply
  • testbug00 - Thursday, March 19, 2015 - link

    Laptop displays. Laptop displays. Laptop displays. Being able to lower the refresh rate when you don't need it higher is something nearly every laptop could use. Currently there are no implementations of Freesync/Async that go down to 9Hz, but, well... That's power savings! Reply
  • Zan Lynx - Wednesday, March 25, 2015 - link

    http://www.intel.com/content/dam/doc/white-paper/p...

    Refresh rate switching is definitely part of it.

    And tablet and phone chipsets go as far as having no refresh at all. The display only updates when there is a new frame. The tablets even use a power-saving simple frame buffer / LCD driver and turn off the render hardware entirely.
    Reply
  • anubis44 - Tuesday, March 24, 2015 - link

    nVidia will buckle. It's inevitable. They can't stand against the entire industry, and AMD has the entire industry behind them with this. Jen Hsun knows he's already lost this battle, and he's just out to milk G-Sync for whatever he can get, for as long as he can get it. It's only a short matter of time before somebody hacks the nVidia drivers and makes them work with FreeSync, a la the old custom Omega ATI drivers. How appealing will it be to pay extra for G-Sync monitors once custom nVidia drivers exist that work with the much wider range of FreeSync monitors? Reply
  • chizow - Tuesday, March 24, 2015 - link

    LOL, yes the thought of having to use a hacked driver to use an inferior solution leading to Nvidia reversing course on G-Sync is a thought only an AMD fan could possibly find palatable.

    G-Sync isn't going anywhere, especially in light of all the problems we are seeing with FreeSync.
    Reply
  • Black Obsidian - Thursday, March 19, 2015 - link

    Of course FreeSync is better than Gsync because it's open.
    Royalty cost to GPU-maker to support FreeSync is literally $0. That makes future Intel or nVidia GPUs a driver update away from supporting FreeSync. Compare to Gsync, at a royalty cost greater than zero, assuming nVidia would license it at all.
    Scaler cost to LCD-makers to support FreeSync appears to be a maximum of $50 now, quite likely $0 in the long run as it becomes a default feature in all scalers. Compare to Gsync at $200+.

    Take off your fanboy blinders for a moment. Capabilities being equal (as they so far seem to be), a royalty-free solution that's supported by default on future standard hardware is clearly better than a royalty-encumbered solution that requires costly additional hardware, no matter which team is supporting which one.
    Reply

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