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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junky77 - Thursday, March 19, 2015 - link
Girls, what about laptops..medi03 - Thursday, March 19, 2015 - link
It's lovely how the first page of the article about FreeSync talks exclusively about nVidia.JarredWalton - Thursday, March 19, 2015 - link
It's background information that's highly pertinent, and if "the first page" means "the first 4 paragraphs" then you're right... but the last two talk mostly about FreeSync.Oxford Guy - Thursday, March 19, 2015 - link
I love how the pricing page doesn't anything to address a big problem with both FreeSync and G-Sync -- the assumption that people want to replace the monitors they already have or have money to throw away to do so.I bought an $800 BenQ BL3200PT 32" 1440 A-MVA panel and I am NOT going to just buy another monitor in order to get the latest thing graphics card companies have dreamt up.
Companies need to step up and offer consumers the ability to send in their panels for modification. Why haven't you even thought of that and mentioned it in your article? You guys, like the rest of the tech industry, just blithely support planned obsolescence at a ridiculous speed -- like with the way Intel never even bothered to update the firmware on the G1 ssd to give it TRIM support.
People have spent even more money than I did on high-quality monitors -- and very recently. It's frankly a disservice to the tech community to neglect to place even the slightest pressure on these companies to do more than tell people to buy new monitors to get basic features like this.
You guys need to start advocating for the consumer not just the tech companies that send you stuff.
JarredWalton - Thursday, March 19, 2015 - link
While we're at it: Why don't companies allow you to send in your old car to have it upgraded with a faster engine? Why can't I send in my five year old HDTV to have it turned into a Smart TV? I have some appliances that are getting old as well; I need Kenmore to let me bring in my refrigerator to have it upgraded as well, at a fraction of the cost of a new one!But seriously, modifying monitors is hardly a trivial affair and the only computer tech that allows upgrades without replacing the old part is... well, nothing. You want a faster CPU? Sure, you can upgrade, but the old one is now "useless". I guess you can add more RAM if you have empty slots, or more storage, or an add-in board for USB 3.1 or similar...on a desktop at least. The fact is you buy technology for what it currently offers, not for what it might offer in the future.
If you have a display you're happy with, don't worry about it -- wait a few years and then upgrade when it's time to do so.
Oxford Guy - Friday, March 20, 2015 - link
"Old" as in products still being sold today. Sure, bud.Oxford Guy - Friday, March 20, 2015 - link
Apple offered a free upgrade for Lisa 1 buyers to the Lisa 2 that included replacement internal floppy drives and a new fascia. Those sorts of facts, though, are likely to escape your attention because it's easier to just stick with the typical mindset the manufacturers, and tech sites, love to endorse blithely --- fill the landfills as quickly as possible with unnecessary "upgrade" purchases.Oxford Guy - Friday, March 20, 2015 - link
Macs also used to be able to have their motherboards replaced to upgrade them to a more current unit. "The only computer tech that allows upgrades without replacing the old part is... well, nothing." And whose mindset is responsible for that trend? Hmm? Once upon a time people could actually upgrade their equipment for a fee.Oxford Guy - Friday, March 20, 2015 - link
The silence about my example of the G1 ssd's firmware is also deafening. I'm sure it would have taken tremendous resources on Intel's part to offer a firmware patch!JarredWalton - Friday, March 20, 2015 - link
The G1 question is this: *could* Intel have fixed it via a firmware update? Maybe, or maybe Intel looked into it and found that the controller in the G1 simply wasn't designed to support TRIM, as TRIM didn't exist when the G1 was created. But "you're sure" it was just a bit of effort away, and since you were working at Intel's Client SSD department...oh, wait, you weren't. Given they doubled the DRAM from 16MB to 32MB and switched controller part numbers, it's probable that G1 *couldn't* be properly upgraded to support TRIM:http://www.anandtech.com/show/2808/2
So if that's the case, it's sounds a lot like Adaptive Sync -- the standard didn't exist when many current displays were created, and it can't simply be "patched in". Now you want existing displays that are already assembled to be pulled apart and upgraded. That would likely cost more money than just selling the displays at a discount, as they weren't designed to be easily disassembled and upgraded.
The reality of tech is that creating a product that can be upgraded costs time and resources, and when people try upgrading and mess up it ends up bringing in even more support calls and problems. So on everything smaller than a desktop, we've pretty much lost the ability to upgrade components -- at least in a reasonable and easy fashion.
Is it possible to make an upgradeable display? I suppose so, but what standards do you support to ensure future upgrades? Oh, you can't foresee the future so you have to make a modular display. Then you might have the option to swap out the scaler hardware, LCD panel, maybe even the power brick! And you also have a clunkier looking device because users need to be able to get inside to perform the upgrades.