NVIDIA recently shed some more light on some of the features regarding its GeForce RTX 30 series graphics cards during a Q&A session held over at the official NVIDIA subreddit .

Few NVIDIA employees answered questions of the community which were related to Ampere GPUs, and the new features implemented by Nvidia. The recent Geforce live event announcement of the Ampere RTX series did not provide many details on the new features, as the company focused more on the product design and pricing of these cards. There were almost 2000 comments and answers in this session. But we still need to wait for independent reviewers to get more technical info on the Ampere lineup. Let us start with the Q&A session.

When the slide says RTX 3070 is equal or faster than 2080 Ti, are we talking about traditional rasterization or DLSS/RT workloads? Very important if you could clear it up, since no traditional rasterization benchmarks were shown, only RT/DLSS supporting games. 

[Justin Walker] We are talking about both. Games that only support traditional rasterization and games that support RTX (RT+DLSS). You can see this in our launch article here.

Does Ampere support HDMI 2.1 with the full 48Gbps bandwidth?

[Qi Lin] Yes. The NVIDIA Ampere Architecture supports the highest HDMI 2.1 link rate of 12Gbs/lane across all 4 lanes, and supports Display Stream Compression (DSC) to be able to power up to 8K, 60Hz in HDR.

Could you elaborate a little on this doubling of CUDA cores? How does it affect the general architectures of the GPCs? How much of a challenge is it to keep all those FP32 units fed? What was done to ensure high occupancy?

[Tony Tamasi] One of the key design goals for the Ampere 30-series SM was to achieve twice the throughput for FP32 operations compared to the Turing SM. To accomplish this goal, the Ampere SM includes new datapath designs for FP32 and INT32 operations. One datapath in each partition consists of 16 FP32 CUDA Cores capable of executing 16 FP32 operations per clock. Another datapath consists of both 16 FP32 CUDA Cores and 16 INT32 Cores. As a result of this new design, each Ampere SM partition is capable of executing either 32 FP32 operations per clock, or 16 FP32 and 16 INT32 operations per clock. All four SM partitions combined can execute 128 FP32 operations per clock, which is double the FP32 rate of the Turing SM, or 64 FP32 and 64 INT32 operations per clock.

Doubling the processing speed for FP32 improves performance for a number of common graphics and compute operations and algorithms. Modern shader workloads typically have a mixture of FP32 arithmetic instructions such as FFMA, floating point additions (FADD), or floating point multiplications (FMUL), combined with simpler instructions such as integer adds for addressing and fetching data, floating point compare, or min/max for processing results, etc. Performance gains will vary at the shader and application level depending on the mix of instructions. Ray tracing denoising shaders are good examples that might benefit greatly from doubling FP32 throughput.

Doubling math throughput required doubling the data paths supporting it, which is why the Ampere SM also doubled the shared memory and L1 cache performance for the SM. (128 bytes/clock per Ampere SM versus 64 bytes/clock in Turing). Total L1 bandwidth for GeForce RTX 3080 is 219 GB/sec versus 116 GB/sec for GeForce RTX 2080 Super.

Like prior NVIDIA GPUs, Ampere is composed of Graphics Processing Clusters (GPCs), Texture Processing Clusters (TPCs), Streaming Multiprocessors (SMs), Raster Operators (ROPS), and memory controllers.

The GPC is the dominant high-level hardware block with all of the key graphics processing units residing inside the GPC. Each GPC includes a dedicated Raster Engine, and now also includes two ROP partitions (each partition containing eight ROP units), which is a new feature for NVIDIA Ampere Architecture GA10x GPUs. More details on the NVIDIA Ampere architecture can be found in NVIDIA’s Ampere Architecture White Paper, which will be published in the coming days.

Any idea if the dual airflow design is going to be messed up for inverted cases? More than previous designs? Seems like it would blow it down on the cpu. But the CPU cooler would still blow it out the case. Maybe it’s not so bad.

Second question. 10x quieter than the Titan for the 3090 is more or less quieter than a 2080 Super (Evga ultra fx for example)?

[Qi Lin] The new flow through cooling design will work great as long as chassis fans are configured to bring fresh air to the GPU, and then move the air that flows through the GPU out of the chassis. It does not matter if the chassis is inverted.

The Founders Edition RTX 3090 is quieter than both the Titan RTX and the Founders Edition RTX 2080 Super. We haven’t tested it against specific partner designs, but I think you’ll be impressed with what you hear… or rather, don’t hear. 🙂

Will the 30 series cards be supporting 10bit 444 120fps ? Traditionally Nvidia consumer cards have only supported 8bit or 12bit output, and don’t do 10bit. The vast majority of hdr monitors/TVs on the market are 10bit.

[Qi Lin] The 30 series supports 10bit HDR. In fact, HDMI 2.1 can support up to 8K@60Hz with 12bit HDR, and that covers 10bit HDR displays.

What breakthrough in tech let you guys massively jump to the 3xxx line from the 2xxx line? I knew it would be scary, but it’s insane to think about how much more efficient and powerful these cards are. Can these cards handle 4k 144hz?

[Justin Walker] There were major breakthroughs in GPU architecture, process technology and memory technology to name just a few. An RTX 3080 is powerful enough to run certain games maxed out at 4k 144fps – Doom Eternal, Forza 4, Wolfenstein Youngblood to name a few. But others – Red Dead Redemption 2, Control, Borderlands 3 for example are closer to 4k 60fps with maxed out settings.

Will customers find a performance degradation on PCIE 3.0?

System performance is impacted by many factors and the impact varies between applications. The impact is typically less than a few percent going from a x16 PCIE 4.0 to x16 PCIE 3.0. CPU selection often has a larger impact on performance.We look forward to new platforms that can fully take advantage of Gen4 capabilities for potential performance increases.

How bad would it be to run the 3080 off of a split connector instead of two separate cable. would it be potentially dangerous to the system if I’m not overclocking?

The recommendation is to run two individual cables. There’s a diagram here. https://www.nvidia.com/en-us/geforce/graphics-cards/30-series/rtx-3080/?nvmid=systemcomp

 RTX IO:

Could we see RTX IO coming to machine learning libraries such as Pytorch? This would be great for performance in real-time applications

[Tony Tamasi] NVIDIA delivered high-speed I/O solutions for a variety of data analytics platforms roughly a year ago with NVIDIA GPU DirectStorage. It provides for high-speed I/O between the GPU and storage, specifically for AI and HPC type applications and workloads. For more information please check out: https://developer.nvidia.com/blog/gpudirect-storage/

Does RTX IO allow use of SSD space as VRAM? Or am I completely misunderstanding?

[Tony Tamasi] RTX IO allows reading data from SSD’s at much higher speed than traditional methods, and allows the data to be stored and read in a compressed format by the GPU, for decompression and use by the GPU. It does not allow the SSD to replace frame buffer memory, but it allows the data from the SSD to get to the GPU, and GPU memory much faster, with much less CPU overhead.

Will there be a certain ssd speed requirement for RTX I/O?

[Tony Tamasi] There is no SSD speed requirement for RTX IO, but obviously, faster SSD’s such as the latest generation of Gen4 NVMe SSD’s will produce better results, meaning faster load times, and the ability for games to stream more data into the world dynamically. Some games may have minimum requirements for SSD performance in the future, but those would be determined by the game developers. RTX IO will accelerate SSD performance regardless of how fast it is, by reducing the CPU load required for I/O, and by enabling GPU-based decompression, allowing game assets to be stored in a compressed format and offloading potentially dozens of CPU cores from doing that work. Compression ratios are typically 2:1, so that would effectively amplify the read performance of any SSD by 2x.

Will the new GPUs and RTX IO work on Windows 7/8.1?

[Tony Tamasi] RTX 30-series GPUs are supported on Windows 7 and Windows 10, RTX IO is supported on Windows 10.

I am excited for the RTX I/O feature but I partially don’t get how exactly it works? Let’s say I have a NVMe SSD, a 3070 and the latest Nvidia drivers, do I just now have to wait for the windows update with the DirectStorage API to drop at some point next year and then I am done or is there more?

[Tony Tamasi] RTX IO and DirectStorage will require applications to support those features by incorporating the new API’s. Microsoft is targeting a developer preview of DirectStorage for Windows for game developers next year, and NVIDIA RTX gamers will be able to take advantage of RTX IO enhanced games as soon as they become available.

RTX Broadcast:

What is the scope of the “Nvidia Broadcast” program? Is it intended to replace current GFE/Shadowplay for local recordings too?

[Gerardo Delgado] NVIDIA Broadcast is a universal plugin app that enhances your microphone, speakers and camera with AI features such as noise reduction, virtual background, and auto frame. You basically select your devices as input, decide what AI effect to apply to them, and then NVIDIA Broadcast exposes virtual devices in your system that you can use with popular livestream, video chat, or video conference apps. NVIDIA Broadcast does not record or stream video and is not a replacement for GFE/Shadowplay

Jason, Will there be any improvements to the RTX encoder in the Ampere series cards, similar to what we saw for the Turing Release? I did see info on the Broadcast software, but I’m thinking more along the lines of improvements in overall image quality at same bitrate.

[Jason Paul] Hi Carmen813, for RTX 30 Series, we decided to focus improvements on the video decode side of things and added AV1 decode support. On the encode side, RTX 30 Series has the same great encoder as our RTX 20 Series GPU. We have also recently updated our NVIDIA Encoder SDK. In the coming months, livestream applications will be updating to this new version of the SDK, unlocking new performance options for streamers.

I would like to know more about the new NVENC — were there any upgrades made to this technology in the 30 series? It seems to be the future of streaming, and for many it’s the reason to buy nvidia card rather than any other.

[Gerardo Delgado] The GeForce RTX 30 Series leverages the same great hardware encoder as the GeForce RTX 20 Series. We have also recently updated our Video Codec SDK to version 10.0. In the coming months, applications will be updating to this new version of the SDK, unlocking new performance options.

Regarding AV1 decode, is that supported on 3xxx series cards other than the 3090? In fact can this question and dylan522p question on support level be merged into: What are the encode/decode features of Ampere and do these change based on which 3000 series card is bought?

[Gerardo Delgado] All of the GeForce RTX 30 Series GPUs that we announced today have the same encoding and decoding capabilities:

– They all feature the 7th Gen NVIDIA Encoder (the one that we released with the RTX 20 Series), which will use our newly released Video Codec SDK 10.0. This new SDK will be integrated in the coming months by the live streaming apps, unlocking new presets with more performance options.

– They all have the new 5th Gen NVIDIA Decoder, which enables AV1 hardware accelerated decode on GPU. AV1 consumes 50% less bandwidth and unlocks up to 8K HDR video playback without a big performance hit on your CPU. 

NVIDIA Reflex:

Will Nvidia Reflex be a piece of hardware in new monitors or will it be a software that other nvidia gpus can use?

[Seth Schneider] NVIDIA Reflex is both. The NVIDIA Reflex Latency Analyzer is a revolutionary new addition to the G-SYNC Processor that enables end to end system latency measurement. Additionally, NVIDIA Reflex SDK is integrated into games and enables a Low Latency mode that can be used by GeForce GTX 900 GPUs and up to reduce system latency. Each of these features can be used independently.

Will Nvidia reflex work with pascal Gpus or is this only a Turing/Ampere feature?

It will work with 900 series+ GPUs, including RTX 20-series