Digital Foundry Article Technical Discussion [2020]

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I'm not convinced any of the Xbox Velocity Architecture is anything more than a rebranding of HBCC.

It definitely does sound like a piece of it. I’m really curious how the texture paging works because it sounds a lot like a virtual texture tile cache.
 
"Primitive shaders" are a nice way to implement "mesh shaders" in D3D lingo and it's great for minimizing codebase maintenance from a developer perspective. Whilst this specific implementation may not nearly offer as high of a geometry throughput compared to the current PC hardware implementation, it has the advantage of a less explicit programming model and thus it's more likely to hit the fast-paths in the compiler/hardware without having to introduce invasive graphics code changes.
 
Based on the variable CPU/GPU clock scenarios Sony is describing, definitely seems like a reaction to try and narrow the spec sheet gap with Series X. Similar to the pre-launch clock changes MS made for the Xbox One. More convinced than ever that the original spec was 9.2TFLOPS, and they squeezed a bit more clock out of the design. Although it doesn't seem like it's actually possible to get 10.2 under a fully loaded CPU/GPU scenario.
 
Please read the full DF articles for each console @ https://www.eurogamer.net/articles/...ies-x-specs-comparison-cpu-gpu-storage-tflops

PlayStation 5 vs Xbox Series X specs: CPU, GPU, storage and more compared
These specs aren't the full story - but they're still an interesting point of comparison.

In the run-up to the reveal of PlayStation 5 and Xbox Series X, there was intense speculation over the hardware that powers each machine. How many teraflops would each next-gen console possess? Which would have the higher CPU clocks? Would both make use of NVMe storage, and what would external storage look like? Now, both Microsoft and Sony have revealed their core specifications, and we finally have a good idea of what each machine looks like on the inside.

The table below collects the most important specifications for each machine, incorporating CPU and GPU architecture and performance, storage solutions, backwards compatibility and more. These specs aren't the full story by any means, but they're still a fascinating point of comparison - and an important backdrop to the larger discussions around the reveals of the Xbox Series X and the Sony PlayStation 5.

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Now it's all up to price, both at the same price? Why the odd 825Gb ssd for ps5 btw? No expension cards either there it seems. Will we have to buy NVME SSD's, like for the PC? Maybe one could stick some ultra fast optane in the ps5.
 
Now it's all up to price, both at the same price? Why the odd 825Gb ssd for ps5 btw? No expension cards either there it seems. Will we have to buy NVME SSD's, like for the PC? Maybe one could stick some ultra fast optane in the ps5.
Maybe they need more redundancy :?:
 
@Dictator how many followup deep dive videos to expect for PS5 after today's reveal?

and good stuff on the Minecraft DXR vid!
 
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Must be busy times for DF, new consoles, gpus, cpus, intel entering gpu space, ray tracing.... new games., and different console specs so df has something to compare when they launch. Oh and VR gaming. Good times.
 
So I'm watching this DF vid about the PS5 specs and I'm really curious about latency to the SSD when they say things like, "it seems like it can read from the disk almost as if it were just RAM". If you look at all of the work that is being done in optimizing game engines, keeping the GPU and CPU working by avoiding cache misses is paramount. The reason is for each step in the cache hierarchy away from the registers and towards HDD/SSD your processor waits longer for data retrieval and your CPU or GPU sits idle. The kind of ballpark numbers on the CPU side is registers are 0/1 clock cycle, L1 is around 5 cycles, L2 is around 10 cycles and RAM is like 200+ cycles. I know the SSD is light years better than an HDD, and looks massively better than any SSD on the market, but they say seek time is "instantaneous" ... but no. Game devs work in nanoseconds as a unit of measure. It's not 0 nanoseconds. Unless it's very close to the same access time reaching RAM, it won't be able to be used like RAM. You really have to look at the latency in terms of clock cycles, and not throughput in seconds. Maybe they do have access times in line with RAM.

The throughput looks very good.

So absolute best case of:
22 GB/s = 22 MB/ms = 352 MB/16ms frame

Average case of:
9 GB/s = 9 MB/ms = 144 MB/16ms frame

PS4 HDD (best case, unrealistic):
100 MB/s = 100 KB/ms = 1.6 MB/16ms frame

PS5 RAM:
440 GB/s = 440 MB/ms = 7 GB/16ms frame

It's been a long time since I've read up on virtual texturing to see how much data you'd need to read on the fly for a 4k framebuffer to make sure you don't have texture pop-in like Rage.
 
I'm curious if, given the CU advantage MS has, if they will also have a proportional ROP advantage. If not, given Sony's clock speed advantage, they would also have a fill rate advantage even if they lag behind in flops.
 
Dedicated. It's a modified CU that's been repurposed for audio. So they probably leveraged all of the work AMD had done running audio on the GPU, but then improved it by removing it from the GPU and streamlining it.

Yeah, it has no cache and only uses LS managed by DMA like and SPE in the Cell processor.
 
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