AMD’s driver software finally changes names and designs today, moving away from almost a decade of having to stare at Catalyst Control Center and deal with its weird idiosyncrasies and strange behaviour. The move to having the driver software be developed using .net was even more perplexing, with important options for some things being buried under layers of menu options, adding on to the bloat and increasing the load times as newer versions of the driver got released. Today, that’s all changing for AMD with the release of Radeon Software Crimson, and I feel justified in saying that this is AMD finally on the mend, getting focused on the things that matter, and being as aggressive as possible with software rollouts and new features. Hit the jump for more.
Most of what you need to know about the release of Crimson has already been said in my previous article about the driver’s reveal by AMD. The important parts to take away are one, that it’s designed in Qt and has a scalable interface and two, that it’s going to be the default moving forward, so we’re all a bit saner for this change. It’s fast, even on much slower systems like dual-core Athlon E1 APUs, and it’s very reminiscent of the Modern design that Microsoft pushed with Windows 8 all those years ago. I’ll have my impressions of the software up soon, so I won’t bore you with too many slides today, but there are a few new rabbits coming out of AMD’s hat that need explaining.
This is the first publicly available software driver that targets AMD’s hardware that enables support for LiquidVR. This is AMD’s approach to making VR headsets run with as little overhead as possible. This is pretty much a folding of all of AMD’s current efforts in the VR space to do some advanced techniques on their hardware, like per-GPU rendering to run one half of the VR display on each GPU in your system. It’s a growing and ever-expanding market and while things aren’t quite there yet for public consumption (we’ll have to wait for the Oculus Rift launch to see things really pick up speed), AMD’s work in this space will pay off eventually.
They’re also working on supporting other headsets like the HTC Vive, Razer OSVR, Valve’s SteamVR, and will eventually feature support for all of the smaller VR projects out there. The basics for all these products are the same, so the work AMD’s doing with LiquidVR will apply to just about every one that will pop up on the market in the feature. Note that AMD also specifies that you need to be using a Radeon R9 290 or faster to benefit from this, so they’re pretty much on par with the requirements specified by Oculus.
There are improvements to FreeSync with the release of Crimson, notably low framerate compensation for frame rates below the monitor’s supported refresh zone, as well as variable refresh rate support through HDMI, which has been technically possible for about six months in AMD’s labs behind closed scenes. But that’s not the most interesting point on this slide.
With the release of Crimson, AMD finally has a working approach to Crossfire in DirectX 9 games, something which the company hasn’t managed to address for the last three years. Coupled in with that work, but not announced by the company, is frame metering for older DirectX 9 games, which means that you’ll see smoother frame delivery and less variation in the frame rate from one moment to the next. AMD doesn’t have the same thing planned for games running on OpenGL, but they might surprise us in the future.
Here’s where things get tricky. AMD’s low framerate compensation (LFC) feature in the Crimson software driver isn’t really well documented. When I was listening in to the conference call, I was told that the way LFC works is by inserting individual frames in between the game’s output to compensate for the lower frame rate, helping to make things smoother. But seeing this slide again, I’m led to believe that AMD has chosen the same route as NVIDIA.
Basically, if your FreeSync-enabled monitor supports a minimum of 30fps, which corresponds to a 30Hz refresh rate, and the game dips to 20fps, the GPU will adjust the monitor’s refresh rate to 40Hz to avoid the tearing and judder you’d see with V-Sync off when below the supported range. You can optionally turn V-Sync off below the supported range, and the GPU will still alter the monitor’s refresh rate, but you won’t get the smoother motion with it off.
Edit: Looking at PC Perspective’s write-up about Crimson, they’ve interpreted things differently when it comes to LFC, and have discovered that AMD’s method is software-driven and does indeed rely on inserting frames into the display chain to make up for the frame rate drop. How this ends up working out remains to be seen, but AMD is basically forwarding a copy of the previous frame to the monitor to make up for the low fps, which might give you a V-Sync-like delay in animations and the information on the display.
On the mobile side, AMD has also changed how they approach resolution scaling for high-density displays. If your laptop display has its resolution set to 1920 x 1080, but has a DPI of 150, you can turn on VSR in the drivers to switch the resolution up to 2560 x 1440. AMD currently doesn’t handle this very well with the Catalyst drivers, which is one of the reasons why notebook vendors have stuck to Intel and NVIDIA for so long.
What AMD doesn’t say is that if you wanted this working on a notebook or a desktop monitor, it would need to have a diagonal size of 14 inches and a native resolution of 1920 x 1080. As you can imagine, notebooks with that kind of setup are rather expensive. There’s also the fact that none of AMD’s APUs for mobile applications support VSR at this time (that’s a hardware, rather than software limitation), which means that this announcement benefits very, very few people.
With Shader Caching, the drivers can pre-fetch the shaders needed for a game and hold it in system memory, decreasing level load times for games that have engines that rely heavily on shader resources. What’s happening behind the scenes is that AMD’s drivers are caching the compiled shaders for your most played games, so that the GPU doesn’t have to recompile them later on when you next boot up the game, or go to a specific level.
I can imagine that this will pay some serious dividends for games like Watch_Dogs, which was heavily criticised by AMD and NVIDIA users because of how the game compiles shaders twice to save on VRAM. Shader caching is a global and per-game feature you can turn off or on in the drivers.
Linux performance improvements! Oh happy day. I’m sure quite a lot of people will be appreciative of AMD’s continued work to make gaming on Linux a smooth experience, and AMD’s been dragging their feet of late with improvements to their performance in OpenGL titles on Linx. A 55% performance improvement in Total War (they don’t mention which one) is nothing to sneeze at. Keep your eyes peeled on Phoronix’s feed to see their performance tests on Linux in the coming weeks.
All of the benefits seen here in Crimson will eventually find their way into Linux, if they haven’t already, since the driver software is now written in Qt. There’s no pending release for the Linux version of Radeon Software Crimson, so it might launch today, or it might launch in a few week’s time.
The last, and probably most important change, affects those of you playing competitive games using AMD graphics hardware. With V-Sync turned on in AMD’s tests, the Catalyst driver would only update the mouse cursor’s position every 51 milliseconds or so (something I’ve personally experienced), which means that there are three frames of latency in between when you move the mouse, and when the drivers update the cursor’s position in-game. Now this happens with every frame rendered, which means that there’s effectively less latency introduced into gameplay with V-Sync turned on. If you’re a CS:GO player, please let me know how well this works out for you, because twitch shooters benefit from this the most.
That’s it for this announcement of the AMD Radeon Software Crimson edition release. I’ll have a deeper look into some of the driver’s features along with screenshots up in a bit, which you can look through while downloading the software. Are you excited, or at least eager to see the end of Catalyst? Let me know in the comments below!
Further reading: AMD Community
Download the drivers: AMD Support