AMD Announces Radeon RX 5700 XT & RX 5700: The Next Gen of AMD Video Cards Starts on July 7th At $449/$379
by Ryan Smith on June 10, 2019 7:20 PM ESTA Quick Note on Architecture & Features
With pages upon pages of architectural documents still to get through in only a few hours, for today’s launch news I’m not going to have the time to go in depth on new features or the architecture. So I want to very briefly hit the high points on what the major features are, and also provide some answers to what are likely to be some common questions.
Starting with the architecture itself, one of the biggest changes for RDNA is the width of a wavefront, the fundamental group of work. GCN in all of its iterations was 64 threads wide, meaning 64 threads were bundled together into a single wavefront for execution. RDNA drops this to a native 32 threads wide. At the same time, AMD has expanded the width of their SIMDs from 16 slots to 32 (aka SIMD32), meaning the size of a wavefront now matches the SIMD size. This is one of AMD’s key architectural efficiency changes, as it helps them keep their SIMD slots occupied more often. It also means that a wavefront can be passed through the SIMDs in a single cycle, instead of over 4 cycles on GCN parts.
In terms of compute, there are not any notable feature changes here as far as gaming is concerned. How things work under the hood has changed dramatically at points, but from the perspective of a programmer, there aren’t really any new math operations here that are going to turn things on their head. RDNA of course supports Rapid Packed Math (Fast FP16), so programmers who make use of FP16 will get to enjoy those performance benefits.
With a single exception, there also aren’t any new graphics features. Navi does not include any hardware ray tracing support, nor does it support variable rate pixel shading. AMD is aware of the demands for these, and hardware support for ray tracing is in their roadmap for RDNA 2 (the architecture formally known as “Next Gen”). But none of that is present here.
The one exception to all of this is the primitive shader. Vega’s most infamous feature is back, and better still it’s enabled this time. The primitive shader is compiler controlled, and thanks to some hardware changes to make it more useful, it now makes sense for AMD to turn it on for gaming. Vega’s primitive shader, though fully hardware functional, was difficult to get a real-world performance boost from, and as a result AMD never exposed it on Vega.
Unique in consumer parts for the new 5700 series cards is support for PCI Express 4.0. Designed to go hand-in-hand with AMD’s Ryzen 3000 series CPUs, which are introducing support for the feature as well, PCIe 4.0 doubles the amount of bus bandwidth available to the card, rising from ~16GB/sec to ~32GB/sec. The real world performance implications of this are limited at this time, especially for a card in the 5700 series’ performance segment. But there are situations where it will be useful, particularly on the content creation side of matters.
Finally, AMD has partially updated their display controller. I say “partially” because while it’s technically an update, they aren’t bringing much new to the table. Notably, HDMI 2.1 support isn’t present – nor is more limited support for HDMI 2.1 Variable Rate Refresh. Instead, AMD’s display controller is a lot like Vega’s: DisplayPort 1.4 and HDMI 2.0b, including support for AMD’s proprietary Freesync-over-HDMI standard. So AMD does have variable rate capabilities for TVs, but it isn’t the HDMI standard’s own implementation.
The one notable change here is support for DisplayPort 1.4 Display Stream Compression. DSC, as implied by the name, compresses the image going out to the monitor to reduce the amount of bandwidth needed. This is important going forward for 4K@144Hz displays, as DP1.4 itself doesn’t provide enough bandwidth for them (leading to other workarounds such as NVIDIA’s 4:2:2 chroma subsampling on G-Sync HDR monitors). This is a feature we’ve talked off and on about for a while, and it’s taken some time for the tech to really get standardized and brought to a point where it’s viable in a consumer product.
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Phynaz - Tuesday, June 11, 2019 - link
These cards are comparable to Nvidia cards from three years ago, even the price.Gastec - Tuesday, June 11, 2019 - link
So are the RTX 2070 and 2080, comparable to 1080 and 1080Ti but more expensive :)CiccioB - Tuesday, June 11, 2019 - link
If you look at the standard features, yes they are.But Turing packs a lot of new features that old gen GPU s have not, and if these features are going to be used Pascal cards (and much so GCN/Navi) will remain in the dust.
Spunjji - Tuesday, June 11, 2019 - link
By the time a significant number of games come out that make proper use of these features, the current cards will be old news. This is usually true for most new graphics technology (see the GeForce 3 and DirectX 8) but I don't think it's been true to this extent and at such a high cost of entry before. We're in new territory here.CiccioB - Tuesday, June 11, 2019 - link
We are in the territory where console monopoly is lowering the technical level te market can reach.If just one of the two consoles were powered by nvidia HW AMD would already be in the dust and highly regret by its buyer while new games engine would exploit all the new features nvidia has inserted into its GPUs since Maxwell.
In fact, we have a market were AMD struggle to keep up with nvidia HW even though it has all the optimization and choices made for the games to run best on its HW.
And we still have the same geometric complexity of 2012.
Korguz - Tuesday, June 11, 2019 - link
maybe nvidia, is just charging too much to put their GPU tech in a console.. how much would it cost to put even a 2060 into a console ?? i would guess 75% of the cost of the console, would just be the GPU....CiccioB - Wednesday, June 12, 2019 - link
Maybe because nvidai didn't want to sell at discount prices as AMD did just not to be annihilated in the gaming market?Think about that: two consoles one with nvidia and one with AMD HW. Now just think which one would have netter graphics and features.
Korguz - Wednesday, June 12, 2019 - link
or maybe because.. ALL your precious nvidia cares about.. is its PROFITS.. or are you to blind of a nvidia fan boy to see this aspect ??? my guess.. you are... and.. have more money then brains." two consoles one with nvidia and one with AMD HW. Now just think which one would have netter graphics and features. " ok.. and how about you think.. which would cost A LOT more then the other one because it has nvidia inside it?? ever think about that ?? as YOU said your self : " New features have a cost " and while its easy to pass that cost on to the consumer with a discrete video card.. that wont work in the console market, but when you think with your wallet.. and not your brain.. this is what happens...
CiccioB - Friday, June 14, 2019 - link
All companies care about their PROFITS, and I may shock you that AMD does too!!!They all sell the products at the best price*potential piece sold at that price to maximize their returns.
Guess waht?
nvidia can apply a higher price becuase their products have higher value.
AMD has to apply a low price because they sell crap HW that has value only whan at discount.
It's a basic economical law.
Now that you have learnt it, you can return play at BF5 at 120FPS but with only 10 polygons on the screen with your Vega card.
Korguz - Friday, June 14, 2019 - link
higher price because their products have higher value.?? BS... they charge that, because they can, and just want profits. but you dont understand that.. cause your are just a young punk kid, with more money then brains, with no financial responsibility, living off mommy and daddy.... when you grow up, and get a mortgage, car payments, and kids.. then maybe you will start to understand the value of money and realize spending 1200 or more on a video card.. is not as important has being able to feed your children, and provide a roof over their heads, fanboy