Nvidia rethinks the graphics card with the RTX 2080September 14, 2018
Nvidia unveiled its new Turing architecture and RTX 2080 graphics cards last month with a big promise of “six times more performance” than the previous generation, and the new ability to support real-time ray tracing in modern games. We’ve seen performance claims, some details about the Turing technical architecture, and many PC gamers trying to calculate how these new cards will actually perform, but I sat down with Nvidia last month to get an in-depth look at the new Turing architecture that’s powering this next generation of cards. It’s fair to say that there’s a lot going on.
The big new feature of Nvidia’s Turing architecture is the ability to support real-time ray tracing in games. Ray tracing is a rendering technique used by movie studios to generate light reflections and cinematic effects. Cars, released back in 2006, was the first extensively ray-traced movie, and many studios now use ray tracing in modern films. Even rendering tools like Adobe AfterEffects, Maya, and 3ds max all support some form of ray tracing, and it’s a technique that’s considered the “holy grail” for video games.
Nvidia has spent 10 years working on ray tracing for its Turing architecture, and it’s clear from the various demos that this isn’t just marketing jargon. Nvidia is starting to introduce ray tracing with the RTX 2080, and some of the early demonstrations have been impressive but limited to certain games. Nvidia’s Battlefield V demo showed off some real-world examples of how the game will be rendered more movie-like, with reflections from explosions on nearby cars and flames that will also reflect off of the metal on guns or even diffuse into the wooden parts of older guns. It’s impressive stuff when you see it up close in a particular part of a game or compare it side by side with a scene that isn’t ray-traced.
Turing sees Nvidia introduce new Tensor cores and RT cores. The RT cores are dedicated to ray tracing, while the tensor cores will be used for Nvidia’s AI work in games. Turing also includes some big changes to the way GPU caches work. Nvidia has moved to a unified memory structure with larger unified L1 caches and double the amount of L2 cache. It’s essentially a rewrite of the memory architecture, and the company claims the result is 50 percent performance improvement per core. Nvidia has also moved to GDDR6 with its RTX 2080, which means there’s as much as 50 percent higher effective bandwidth for games.
All of these big platform changes make it more than a little difficult to determine how significant any performance gains will be for regular PC gamers. “This is a new computing model, so there’s a new way to think about performance,” said Nvidia CEO Jensen Huang at the company’s unveiling event in Germany last month. That new way to think about performance underlines many of the changes that Nvidia is making with RTX, in an era where Moore’s law is over. It’s not just how much faster a CPU or GPU is anymore that matters, nor the number of cores it has. It’s now the big architectural changes that will make a difference for both image quality and performance for years to come. Nvidia, Intel, AMD, Samsung, Apple, and many others will increasingly need to do more with the existing transistors on chips instead of continuing to shrink their size. Nvidia has clearly realized this inevitability, and it’s time for a change of pace.
Nvidia is offloading some of the work that would normally be handled by the company’s CUDA cores to these separate Tensor and RT cores. Nvidia is also introducing new rendering and texture shading techniques that will allow game developers to avoid having to continually shade every part of a scene when the player moves around. This will help improve performance, but Nvidia is going a step further with the help of supercomputers.
Nvidia Deep Learning Super-Sampling (DLSS) could be the most important part of the company’s performance improvements. DLSS is a method that uses Nvidia’s supercomputers and a game-scanning neutral network to work out the most efficient way to perform AI-powered antialiasing. The supercomputers will work this out using early access copies of the game, with these instructions then used by Nvidia’s GPUs. Think of it like the supercomputer working out the best way to render graphics, then passing that hard-won knowledge onto users’ PCs. It’s a complex process, but the end result should be improved image quality and performance whether you’re playing online or offline.
The real test for DLSS will be how well it improves performance for 4K games. While the GeForce GTX 1080 Ti struggled to hit 60 fps in 4K for modern games, Nvidia is promising some impressive performance gains at 4K with DLSS enabled on the RTX 2080. We only recently received cards for testing, so we’ll be checking to see just how well some of these DLSS games perform in the coming weeks.
Nvidia is really overhauling its entire architecture here, and the way it thinks about graphics cards with Turing and RTX. In the past, Nvidia would be happy to sell you a graphics card because it’s faster, more powerful, and has more memory. That still holds true today, but the conversation is shifting toward new capabilities and optimizations for graphics cards over the raw specs. Whether it’s ray tracing, DLSS, or Nvidia’s many other changes and improvements, you’re buying into this complex new architecture with a promise of what’s to come.
Only 11 games support full ray tracing right now, and 21 games in total (for now) will implement either ray tracing, DLSS, or other RTX platform improvements. Some will obviously implement all three, providing the best performance boosts. Nvidia is also working with Microsoft to bring many of its RTX components to DirectX, but its main rival AMD will also need to help push this new era of ray tracing. AMD supplies the graphics cards for both the PlayStation 4 and Xbox One, and a new generation of consoles is expected in 2020. The hardware inside them will really shape the imminent future of games as developers increasingly look to ensure titles are available across consoles, PCs, and even mobile devices. If the next consoles can’t support real-time ray tracing, then it’s unlikely to be widely adopted across games in the near future.
That’s not going to stop Nvidia, though. The company is taking a big bet on the future of the graphics card. As we enter an era where raw chip speeds don’t tell the whole story, it will be the big overhauls of architecture and clever use of hardware and software that will push the games industry forward. Nvidia has made its gamble, and the dice are now rolling.