The AMD FreeSync Review
by Jarred Walton on March 19, 2015 12:00 PM ESTFreeSync 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.
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chizow - Friday, March 20, 2015 - link
Yeah np, 2nd paragraph after the CCC Picture, it clearly states FreeSync panels begin exhibiting ghosting bleow 60Hz.https://translate.google.com/translate?sl=auto&...
You can thank me later for saving you $500+ on a 1st Gen FreeSync panel with ghosting problems that would frankly make it unusable to most.
I am sure we will see more reviews once reviewers actually get samples they can keep and aren't forced to use in AMD's controlled test environment...
silverblue - Saturday, March 21, 2015 - link
I said plural only because you implied it. More links still required.chizow - Saturday, March 21, 2015 - link
You can use google just as well as I can, I am sure. 2 links are plenty, especially when they actually give photo evidence of the problem.chizow - Monday, March 23, 2015 - link
Another confirmation of the problem from Forbes, with quotes from Petersen:http://www.forbes.com/sites/jasonevangelho/2015/03...
The fact Jarred and AT not only missed this, but have actively made excuses/denied it is pretty appalling as more and more reviewers are making note of the ghosting and flickering problems with FreeSync.
anubis44 - Tuesday, March 24, 2015 - link
@chizow: "Read some actual reviews that clearly show right now FreeSync is the inferior solution."You mean, as opposed to all the 'virtual' reviews we've been reading that all say the same thing: that FreeSync does exactly what G-Sync does, except for free? Clearly, a green goblin lover like yourself must respect techreport.com, a blatantly pro-nVidia website plain and simple, and even their response to FreeSync? I quote Scott Wasson:
"Now, I have only had a few hours with the BenQ XL2730Z (our review sample arrived yesterday afternoon), but my first impressions are just this: AMD has done it. They've replicated that sense of buttery smooth animation that a fast G-Sync display will get you, and they've done it in a way that squeezes the extra costs out of the monitors. This is a very good thing."
I'll repeat that operative part of the quote so you can't possibly overlook or ignore it. AMD has "DONE IT. They've REPLICATED THAT SENSE OF BUTTERY SMOOTH ANIMATION that a fast G-Sync display will get you, and they've done it in a way that SQUEEZES THE EXTRA COSTS OUT OF THE MONITORS."
This is all that the vast legions of gamers are going to care about: same buttery smooth performance, less cost. QED.
chizow - Tuesday, March 24, 2015 - link
Yeah, they are virtual reviews, done in controlled test environments in a limited period of time just as noted in that review. Now that actual live samples are coming in however, a LOT of problems are creeping up outside of the controlled test environments.And before you attack the author's credibility, as I'm sure you will, keep in mind this guy has been a huge AMD advocate in the past:
http://www.forbes.com/sites/jasonevangelho/2015/03...
"Note to readers: I have seen this firsthand on the Acer FreeSync monitor I’m reviewing, and PC Perspective noticed it with 2 additional FreeSync monitors, the BenQ XL2730Z and LG 34UM67. To illustrate the problem they recorded the aforementioned monitors running AMD’s Windmill demo, as well as the same demo running on a G-Sync enabled Asus ROG Swift. Ignore the stuttering you see (this is a result of recording at high speed) and pay attention to the trailing lines, or ghosting. I agree that it’s jarring by comparison."
anubis44 - Tuesday, March 24, 2015 - link
@maximumGPU: Oh, but chizow DOES believe it. He believes that the green goblin on the box is the hallmark of quality, and that nVidia NEVER makes any mistakes, NEVER rips off its customers, and NEVER cheats or lies, or acts deceptively, because 'it's all business'. In other words, he's a sociopath. He BELIEVES G-Sync MUST be better than FreeSync because there's a green goblin-labelled chip in the G-Sync monitor that MUST be doing SOMETHING the FreeSync monitor just cannot do. It just HAS to be better, because he PAID for it. LOLchizow - Tuesday, March 24, 2015 - link
Who cares about all that noise? They still offer the best product at any given price point if you can afford a slightly better product. Only sycophants like you go into the stupid and inane morality of it, same way you begrudge Intel for putting their boot to AMD's neck in the CPU market.Buy what gives you the best product for your money and needs, who cares about the rest.
medi03 - Thursday, March 19, 2015 - link
GSync is a shameless attempt to ban competition.AMD couldn't use it even if it would PAY for it.
On the contrary, FreeSync, being VESA standard, can be freely used by any GPU manufacturer, including Intel and nVidia.
Frenetic Pony - Thursday, March 19, 2015 - link
It's adaptive sync but worse in every way. What is possibly good about it?