Digital Foundry, a site focused on 4K gaming videos, has published the final specs for Microsoft’s upcoming Project Scorpio. 

Richard Leadbetter, a journalist with Digital Foundry was invited to Microsoft for an indepth exclusive preview of the tech under the hood of Microsoft’s anticipated Project Scorpio.

Video hightlights of Rich’s Project Scorpio assessment

Project Scorpio Specs

Project Scorpio Xbox One PS4 Pro
CPU Eight custom x86 cores clocked at 2.3GHz Eight custom Jaguar cores clocked at 1.75GHz Eight Jaguar cores clocked at 2.1GHz
GPU 40 customised compute units at 1172MHz 12 GCN compute units at 853MHz (Xbox One S: 914MHz) 36 improved GCN compute units at 911MHz
Memory 12GB GDDR5 8GB DDR3/32MB ESRAM 8GB GDDR5
Memory Bandwidth 326GB/s DDR3: 68GB/s, ESRAM at max 204GB/s (Xbox One S: 219GB/s) 218GB/s
Hard Drive 1TB 2.5-inch 500GB/1TB/2TB 2.5-inch 1TB 2.5-inch
Optical Drive 4K UHD Blu-ray Blu-ray (Xbox One S: 4K UHD) Blu-ray

Here are some of the key points:

  • “To me, [4K] means a very specific set of things. It’s a lot more than delivering than those eight-million-plus pixels to the screen while playing games,” says Kevin Gammill, Group Program Director of the Xbox Core platform. “It’s about delivering those pixels with 4K assets, so they look great. It’s about delivering those pixels with HDR and wide colour gamut fidelity. It’s about delivering those pixels with no loss of frame-rate compared to the 1080p version of that title – that’s super-important to us. Spatial audio adds to the immersive experience as well: to truly land that gameplay experience, it’s not just about what you see, but what you hear.”
  • “As we landed on 4K, Andrew [Goossen] and team did a pretty deep analysis,” Gammill continues. “We have this developer tool called PIX [Performance Investigator for Xbox]. It lets us do some GPU trace capture. He and his team did a really deep analysis across a breadth of titles with the goal that any 900p or better title would be able to easily run at frame-rate at 4K on Scorpio. That was our big stake in the ground, and so with that we began our work speccing out what the Scorpio Engine is. It’s not a process of calling up AMD and saying I’ll take this part, this part and this part. A lot of really specific custom work went into this.”
  • “We also leveraged the fact that we understand the AMD architecture really, really well now and how well it does on our games,” continues Goossen, “so we were able to go through and examine a lot of the internal queues and buffers and caches and FIFOs that make up this very deep pipeline that, if you can find the right areas that are causing bottlenecks, for very small area [on the processor] we could increase those sizes and get effective wins.”
  • “Those are the big ticket items, but there’s a lot of other configuration that we had to do as well,” says Goossen, pointing to a layout of the Scorpio Engine processor. “As you can see, we doubled the amount of shader engines. That has the effect of improvement of boosting our triangle and vertex rate by 2.7x when you include the clock boost as well. We doubled the number of render back-ends, which has the effect of increasing our fill-rate by 2.7x. We quadrupled the GPU L2 cache size, again for targeting the 4K performance.”
  • “For 4K assets, textures get larger and render targets get larger as well. This means a couple of things – you need more space, you need more bandwidth. The question, though, was how much?” asks Nick Baker, Distinguished Engineer, Silicon. “We’d hate to build this GPU and then end up having to be memory-starved. So all the analysis that Andrew was talking about, we were able to look at the effect of different memory bandwidths, and it quickly led us to needing more than 300GB/s memory bandwidth. So in the end we ended up choosing 326GB/s. On Scorpio we are using a 384-bit GDDR5 interface – that is 12 channels. Each channel is 32 bits.”
  • “So, eight cores, organised as two clusters with a total of 4MB of L2 cache. These are unique customised CPUs for Scorpio running at 2.3GHz. Alluding back to the goals, we wanted to maintain 100 per cent backwards compatibility with Xbox One and Xbox One S while also pushing the performance envelope,” says Nick Baker.
  • “We essentially moved Direct3D 12,” says Goossen. “We built that into the command processor of the GPU and what that means is that, for all the high frequency API invocations that the games do, they’ll all natively implemented in the logic of the command processor – and what this means is that our communication from the game to the GPU is super-efficient.”
  • “On the display output, of course, HDMI 2.0 – we need that for the additional frame-rate for 4K and also HDR and the wide colour gamut,” says Nick Baker. “In addition, we have always believed in having flexible output processing with three output planes so you can have your render target, your overlay dash and video playing. Each one of those has symmetric capabilities in terms of being able to run sampling, so we have a high quality multi-tap filter. As an example, if you render at 4K and you’re going to a 1080p TV, you can use that to do a high quality sample.”
  • “So really, between trying to target a compact design, and also strike overall efficiency and minimise power use, we do a lot of things that are special,” says Leo Del Castillo, general manager of Xbox hardware design. “One of the things we do is we basically fine tune the voltages for each of the chips and optimise them so the chips are getting exactly what they need to get the job done… That drives a much higher degree of efficiency into the system and allows us to get rid of a lot of wasted power that would otherwise come out as heat.”
  • “This is us. This is ForzaTech running 60 frames a second, 4K,” says Turn 10 Studio Software Architect, Chris Tector. “We’re still running with settings that we would have used in Forza 6… but this is also including 4K content… we’ve got authored assets for this set of the models, cars, tracks everything. We pushed it through and made sure the 4K textures were flowing through. We’ve got them all there at the right resolutions and they’re not giving us enough of a bandwidth hit to offset that. If we drop back to when we originally ran and we didn’t have 4K assets, it was maybe one per cent different. We were very much bound on a different point than memory bandwidth. It’s been awesome and this is the point it’s at.”
forza

 

Source: You can find the original entire article at Inside the next Xbox: Project Scorpio tech revealed

 

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