Today AMD finally launches its first Big Navi graphics cards.
AMD releases Radeon RX 6800 series
AMD RDNA 2 Architecture
The Radeon RX 6800 series are built using new architecture codenamed RDNA 2. AMD claims there is a major breakthrough in high-speed design that increases performance-per-watt efficiency and introduces a ‘revolutionary’ Infinity Cache, Navi’s large “L3” cache. The AMD RDNA 2 architecture will support Microsoft 12 Ultimate and all its features. AMD will also offer its own developers tools called FidelityFX for select developers who wish to participate.
AMD confirmed that Navi 21 has a die size of 519.8 mm2 packed with 26.8 billion transistors. The GPU supports HDMI 2.1 with resolutions up to 8k 120Hz. It will support 8K AV1 decoding as well as 8K HEV encoding.
AMD Radeon RX 6800 Series Specifications
AMD Radeon RX 6800 XT is based on Navi 21 XT GPU with 72 Compute Units enabled. This gives a total of 4608 Stream Processors (64 x 72), 288 Texture Units, 128 ROPs, and 72 Ray Accelerators (one for each CU). The graphics card is equipped with 16GB of GDDR6 memory and a 256-bit memory bus. The memory bandwidth of 512 GB/s will increase when 128MB of AMD’s new Infinity Cache will be used. AMD has set the price to 649 USD for this model
The Radeon RX 6800 non-XT features Navi 21 XL GPU with 60 Compute Units (3840 Stream Processors). A 240 Texture Units and 96 ROPs are enabled on this Big Navi variant. There is however no difference when it comes to the memory configuration. The RX 6800 features 16GB GDDR6 memory clocked at 16 Gbps. The full 128MB of Infinity Cache is available as well. This SKU will retail at 579 USD.
| AMD Radeon RX 6000 Series Specifications | |||
|---|---|---|---|
| VideoCardz | Radeon RX 6900XT | Radeon RX 6800XT | Radeon RX 6800 |
| Picture |  | |  |
| GPU | Navi 21 XTX | Navi 21 XT | Navi 21 XL |
| Compute Units | |||
| Stream Processors | |||
| Ray Accelerators | |||
| Texture Units | |||
| ROPs | |||
| Game Clock | |||
| Boost Clock | |||
| Memory | |||
| Infinity Cache | |||
| Memory Clock | |||
| Memory Bandwidth | |||
| Memory Bus | |||
| Total Board Power | |||
| MSRP | |||
| Release Date | December 8 | November 18 | November 18 |
The Performance of Radeon RX 6800 series
AMD released five slides with Radeon RX 6800 series performance claims. Most of them appear to be identical to what was shown at the announcement last month. AMD has not updated the charts to show NVIDIA RTX 3070, which has already been released last month, instead, we have RTX 2080 Ti, the last-gen NVIDIA flagship:
AMD Radeon RX 6800 Performance, Source: AMD
AMD Radeon RX 6800 XT Performance, Source: AMD
AMD also sees the importance of the growing popularity of high-refresh-rate displays. Both RX 6800 graphics cards should provide at least 144 frames per second in select games at 1440p resolution:
AMD RX 6800 Graphics cards design
AMD Radeon RX 6800 and RX 6900 XT are all the same length, 26.7 cm. The graphics cards are thus the same length as NVIDIA GeForce RTX 2080 Ti and GTX 1080 Ti. The RX 6800 non-XT is also the same TDP (250W). All that considered AMD expects users of these two NVIDIA GPUs to upgrade to AMD’s latest RDNA2 graphics cards:
AMD considers its RX 6800 series board design as premium. It features the standard PEG power connectors at the standard position on the PCB, which should help users with better cable management, AMD says. The 14-layer high-performance PCB with 4 layers of 2 ounces of copper will power the 15 power stages:
AMD Smart Access Memory
AMD will allow Ryzen 5000 series CPUs to access the full GPU memory of the Radeon RX 6800 series. This technology is expected to boost the performance from 5% to 11% depending on the workload. This feature is available at launch, but it is currently limited to AMD Ryzen 5000 series CPUs. NVIDIA is already planning to answer this technology with resizable BAR adjustment for its GeForce RTX graphics cards (which is part of the PCI-Express specifications). That said, AMD might unlock this technology for more GPUs and more CPUs.
AMD Infinity Cache
One of the key innovations coming with the Radeon RX 6800 series is the Infinity Cache, a very large (128MB) cache built upon the principles of AMD Zen large L3 cache and its Infinity Fabric technology. The technology allows the game engine to access the data faster and at lower performance/power cost to the GPU. AMD claims that this technology will reduce memory latency by 34%:
AMD Software & Rage Mode
AMD is also bringing overclocking presets to its Radeon Software. A new mode called Rage Mode will be available to Radeon RX 6800 series. This mode will adjust TGP, fan profile, and frequency up to 2310 MHz (boost):
Ray Tracing and Super Resolution
AMD releases two slides with RDNA2 hardware-accelerated ray tracing performance in games and content creation (Blender):
AMD has dedicated few slides to underline the importance of ray tracing in the next-gen gaming experience. AMD RX 6800 series support Micorosft DXR (an open standard) that is already supported by a handful of games. The technology will be accompanied by FidelityFX Denoiser, responsible for improving the quality of ray tracing acceleration.
AMD FidelityFX Super Resolution
AMD confirmed it is working on Super Resolution technology, similar to NVIDIA Deep Learning Super Sampling (DLSS). The company did not confirm when it will be available and in what games.
DirectX 12 Ultimate and FidelityFX
The Radeon RX 6800 series fully support DirectX 12 Ultimate and its core technologies such as mesh shading, sampler feedback and variable rate shading:
Availability
AMD Radeon RX 6800 XT and Radeon RX 6800 will be available for starting from now. The availability of the reference model is expected to be very, very limited. The price of the 6800XT has been set to 649 USD, while the RX 6800 non-XT should cost 579 USD. Custom models based on the RX 6800 series are to launch on November 25th.
