Linux Support Expectations For The AMD Radeon RX 6000 Series

Lisa Su is about to begin the presentation unveiling the much anticipated Radeon RX 6000 "Big Navi" (RDNA 2) graphics cards. This article will be updated live as the event progresses but first up let's recap the current Linux open-source driver state for these forthcoming graphics cards.

Under the codename Sienna Cichlid, the Linux support for the next-generation Navi graphics cards have been underway going back to the middle of the year. There is initial support for the next-gen hardware within the recent released Linux 5.9 kernel and Mesa 20.2. This still puts it just out-of-reach for seeing out-of-the-box support in the likes of Ubuntu 20.10 given the 5.8 kernel so the user must manually move to the newer kernel. At least with the likes of Fedora Workstation 33 there will be Linux 5.9 as a stable release update. Also important to the driver equation is needing to be using LLVM 11.0+ for the GFX10.3 back-end target and also ensuring to have the latest linux-firmware for the binary microcode files needed for GPU initialization.

So at least going into this launch it's great there is at least open-source driver support available but not necessarily easy reach for all users right now. By the time of the spring 2021 Linux distributions like Ubuntu 21.04 there should be nice out-of-the-box support for those wanting good support without any hassles. Or if you are on an enterprise distribution like RHEL/CentOS or SUSE Linux Enterprise or Ubuntu 20.04 LTS, AMD should be providing their usual Radeon Software for Linux packaged driver that ships updated user and kernel-space components for deploying their driver that way.

While there is the first-cut support in Linux 5.9 and Mesa 20.2, generally with all new graphics hardware launches from Intel and AMD it pays off using even more recent code -- namely the latest development code, which right now is on Linux 5.10 and Mesa 20.3. There have been more Sienna Cichlid and Navy Flounder updates in Linux 5.10 and continued work in Mesa 20.3, especially in general in regards to the RADV/ACO driver stack. With RADV/ACO being developed independent of AMD, there may be last minute tweaks needed to this driver stack too.

Thus for the best support and performance users may need to move to Linux 5.10 Git and Mesa 20.3-devel, but once the graphics cards are actually shipping and we have tested the Radeon RX 6000 series we can provide more detailed guidance about the proper Linux support baseline. For Ubuntu users I normally recommend track the Ubuntu Mainline Kernel PPA and Oibaf PPA with new Intel/Radeon graphics.

Anyhow, that's the overall state of the open-source Linux driver support as published right now. Below is the Lisa Su keynote for the Radeon RX 6000 series and my notes will be added below. Stay tuned for Radeon RX 6000 series Linux benchmarking in the near future in seeing how it can stack up to the likes of the GeForce RTX 3080 on Linux.

RDNA 2 is said to offer +50% performance-per-Watt over RDNA(1).

28.6 billion transistors are in Big Navi.

RDNA 2 brings high performance compute units, Infinity Cache, and other advanced features. The compute unit now allows fine-grained clock gating, pipeline changes, and more. The compute units are 30% more energy efficient. The Radeon Infinity Cache is based on the Zen 3 L3 cache.

RDNA 2 can deliver a 30% frequency increase with the same power envelope at 7nm and hits 54% greater performance-per-Watt over RDNA.

RDNA 2 delivers roughly double the performance of the existing Radeon RX Navi/RDNA graphics cards.

RDNA 3 is confirmed to be in design.

The Radeon RX 6800 XT has 72 compute units, 2250MHz boost clock, 128MB infinity cache, 16GB of GDDR6 video memory, and 300 Watt board power. AMD shows the Radeon RX 6800 XT going up against the NVIDIA GeForce RTX 3080 and with lower power consumption.

There is AMD Smart Access technology when pairing RX 6000 series GPUs and Ryzen 5000 series processors. At the moment this does not appear to have any Linux support. (Update: It turns out the functionality does work on Linux as it amounts to resizable BAR support.)

The Radeon RX 6800XT will be available 18 November at $649 USD.

The Radeon RX 6800 series as a step below is a 250 Watt graphics card intended for entry-level 4K performance. The Radeon RX 6800 goes up against the GeForce RTX 2080 Ti. This graphics card will retail for $579 USD.

The Radeon RX 6900XT is the new flagship card. The Radeon RX 6900XT has 80 compute units, 2250MHz boost clock, 128MB infinity cache, 16GB GDDR6, and 300 Watt board power. The Radeon RX 6900XT delivers 65% better performance-per-Watt over the first generation RDNA graphics.

The Radeon RX 6900XT will launch on 8 December at $999 USD.

These are the highlights from today's livestream. Stay tuned for Radeon RX 6000 series Linux benchmarking on Phoronix.