CES — On the show floor here at CES today, I spoke briefly with Nvidia's Tom Petersen, the executive instrumental in the development of G-Sync technology, about the AMD "free sync" demo we reported on yesterday. Alongside the demo, a senior AMD engineering executive asserted that a variable refresh rate capability like G-Sync ought to be possible essentially for free, without adding any extra costs to a display or a PC system. Peterson had several things to say in response to AMD's demo and claims.
He first said, of course, that he was excited to see his competitor taking an interest in dynamic refresh rates and thinking that the technology could offer benefits for gamers. In his view, AMD interest was validation of Nvidia's work in this area.
However, Petersen quickly pointed out an important detail about AMD's "free sync" demo: it was conducted on laptop systems. Laptops, he explained, have a different display architecture than desktops, with a more direct interface between the GPU and the LCD panel, generally based on standards like LVDS or eDP (embedded DisplayPort). Desktop monitors use other interfaces, like HDMI and DisplayPort, and typically have a scaler chip situated in the path between the GPU and the panel. As a result, a feature like variable refresh is nearly impossible to implement on a desktop monitor as things now stand.
That, Petersen explained, is why Nvidia decided to create its G-Sync module, which replaces the scaler ASIC with logic of Nvidia's own creation. To his knowledge, no scaler ASIC with variable refresh capability exists—and if it did, he said, "we would know." Nvidia's intent in building the G-Sync module was to enable this capability and thus to nudge the industry in the right direction.
When asked about a potential VESA standard to enable dynamic refresh rates, Petersen had something very interesting to say: he doesn't think it's necessary, because DisplayPort already supports "everything required" for dynamic refresh rates via the extension of the vblank interval. That's why, he noted, G-Sync works with existing cables without the need for any new standards. Nvidia sees no need and has no plans to approach VESA about a new standard for G-Sync-style functionality—because it already exists.
That said, Nvidia won't enable G-Sync for competing graphics chips because it has invested real time and effort in building a good solution and doesn't intend to "do the work for everyone." If the competition wants to have a similar feature in its products, Petersen said, "They have to do the work. They have to hire the guys to figure it out."
This sentiment is a familiar one coming from Nvidia. The company tends to view its GeForce GPUs and related solutions as a platform, much like the Xbox One or PS4. Although Nvidia participates in the larger PC gaming ecosystem, it has long been guarded about letting its competitors reap the benefits of its work in various areas, from GPU computing to PhysX to software enablement of advanced rendering techniques in AAA games.
Like it or not, there is a certain competitive wisdom in not handing off the fruits of your work to your competition free of charge. That's not, however, how big PC players like Intel and AMD have traditionally handled new standards like USB and x86-64. (Intel in particular has done a lot of work "for everyone.")
If you recall our report from yesterday on this subject, Nvidia and AMD do seem to agree on some of the key issues here. Both firms have told us that the technology to support variable refresh rates exists in some cases already. Both have said that the biggest challenge to widespread adoption of the tech on the desktop is support among panel (and scaler ASIC) makers. They tend to disagree on the best means of pushing variable refresh tech into wider adoption. Obviously, after looking at the landscape, Nvidia chose to build the G-Sync module and enable the feature itself.
My sense is that AMD will likely work with the existing scaler ASIC makers and monitor makers, attempting to persuade them to support dynamic refresh rates in their hardware. Now that Nvidia has made a splash with G-Sync, AMD could find this path easier simply because monitor makers may be more willing to add a feature with obvious consumer appeal. We'll have to see how long it takes for "free sync" solutions to come to market. We've seen a number of G-Sync-compatible monitors announced here at CES, and most of them are expected to hit store shelves in the second quarter of 2014.