Hot Chips 32, XSX Architecture Deep Dive

Yeah, this console is quite a beast, even better than the already fantastic Xbox One X. Forza Motorsport 7 @ 4K/60fps is the sort of marvel that I did not expect to see this generation, so I can only salivate at what a GPU with about twice the TF, raytracing, SSD, etc. will do.

I’m still in awe of what my One X can produce, in some cases better than my i9, 40 GB RAM, Vega 48 system; console optimization goes a lot further than the PCMR would care to admit. I just need the price and preorder date at this point for the Series X.

Digital Foundry analysis


It’s easy to forget just how powerful the SX will actually be. It is beyond all expectation from about 18 months ago. I personally think it will render any talk of power, performance or multiplat comparison to be minimised because these things will not be in favour of the PS5 at all.


Written article available here for those that prefer to read these sorts of things.


Is it wrong to assume that XSX has 52*4 = 208 RT cores?

And then if multiply 208 RT cores with there frequency of 1.825 GHz i.e,

208*1.825=379.6 ~ 380

This calculation is equal to what RT performance is mentioned for XSX.

Will it be wrong to apply the above formula for the 2080ti’s 68 RT cores running at 1.545GHz max frequency reported by nvidia as well? I.e, 68*1.545= 105

I got the impression that there are 52 Rt cores each able to perform 4 ops per clock. But I dunno about Nvidia setup.

It really is the dream wish list of specs: An 8 core CPU clocked up to 3.8Ghz, high speed RAM, SSD, ray tracing and 12tf of GPU power. The only disappointment is that we didn’t get a massive leap in memory but unfortunately that was not on the cards this year.

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I made a thread on digital foundrys xsx hotchips deep dive, maybe it would be a good idea of that thread was merged into this one?


I’m kinda on the fence with Tommy Fisher. He nailed the XSX specs. No one was talking about 52CUs, and he nailed the speed as well. I think he had some kind of inside info, but he was quoting the original GCN PS5 dev kit which were apparently around 13tflops.

Reminder: No insider drama friends. This isn’t the forum for checking receipts on insiders.


The whole system seems so well designed and put together. The design flair is definitely on the inside.

I guess the process is they make a chip, each CU gets tested. Then they bin the ones that don’t have enough usable and keep the rest. Couple of silly questions.

If a chip has more than the required usable does the chip know this and can switch to one if one fails?

Does binning mean literally throw them in bin it could they be used elsewhere?

For Binning, if you look at pc GPU’s, this is how you get the 3080 and the 3080ti. Some are capable of higher speeds or have less production faults so you can use them to the fullest capacity. Those that do not work for a lesser product are then pulled together after testing.

If you have enough that fit inside a category envelope, you can use them in other products or potentially design around the restrictions. You have to pay the same amount for a wafer of chips, no matter how many fail so utilising as many as possible is how they can pull costs down per chip.

For the failed CU question, this is outside my knowledge wheelhouse unfortunately. It may be worth throwing the question to Richard Leadbetter of Digital Foundry

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The XSX is really such a well designed console. MS redeemed themselves on the hardware front with the Xbox One X, and the Series X is just an evolution of the amazing work they did on the XOX. I owned the PS4 Pro, and while it was ok, it was never the quality of hardware the XOX was.

I now really hope MS and the third parties can exploit all of the XSXs abilities.

Microsoft was always about the most powerful console, and they nailed that on the OG Xbox, the 360 and now the XOX and XSX. Now lets get that software nailed bois.


Believe it or not but I was actually a believer in klee, he seemed quite credible, he was former writer for a quite popular gaming mag. I was all set the PS5 was homage to crazy ken and it was going to be some 14tflop beast. It was kinda funny and shocking that its a 9-10tflop machine with a variable cpu + gpu.

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Watching the Digital Foundry breakdown of the Hot Chips presentation makes it even more apparently that the backwards compatibility team is the centerpiece of Xbox hardware design

Those people are freaks of nature and Sony should be doing all in their power to poach them


I was thinking there would be an actual number in NV metrics for RT performance in the video.

NV should list those raw numbers with the ray cast/s lol.

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Series X dev kit with 40GB ob RAM

You are still a bit generous with 9-10tf, better get used to 8,4 wait till Sony reveal the base clock.

To write for a popular game magazine doesn’t mean you understand the context of information given. It was clear from the beginning that for a correct understanding he lacked the foundations. Just like with Reiner and Schreier.