Discussion Google Stadia CPU - what could it possibly be?

[Hans de Vries]

I don't think I've seen that anywhere. I've seen that the GPU uses HBM2, and that there's a total of 16 GB of RAM, and that each node has up to 484GB/s transfer speed. All these things can be true even without a unified pool of HBM 2.

So we can have 8GB of HBM2, and 8GB of DDR4. And there is up to 484GB/s if you're looking at the HBM2 block and not the DDR4 block. The usage of "up to" is actually pretty odd when listing bandwidth, but makes sense when you look at each node as having two separate memory pools. Not to mention, why list HBM2 under GPU header when there's a separate Memory section? That seems pretty telling. The only thing I can think of is because that HBM2 pool is only available to the GPU. It looks like a bit of marketing speak to make the thing look a bit more impressive than it really is.

All kinds of things are possible but they don't make a lot of sense...
Also how can they have a custom Intel CPU (as guessed by some) if Intel is not one of their partners..

This looks much more like a larger (and HBM2) version of the Zhongshan Subor custom console chip.

 

[jpiniero]

Also how can they have a custom Intel CPU (as guessed by some) if Intel is not one of their partners..

Because Intel is embarrassed...

 

[Gideon]

All kinds of things are possible but they don't make a lot of sense...
Also how can they have a custom Intel CPU (as guessed by some) if Intel is not one of their partners..

This looks much more like a larger (and HBM2) version of the Zhongshan Subor custom console chip.

Easy, they plan to ditch it for Zen 2 in the next iteration, therefore do not want to give it publicity. That would also explain AVX2 only as Zen won't support AVX-512 (therefore it's best to avoid it alltogether, or otherwise some devs might start using it and would need to undo it later)

 

[NTMBK]

I suspect version 1 is just Vega 56 alongside a custom-SKU Xeon. Version 2 will probably be something more specialised- I'd expect a semicustom APU.

 

[Hans de Vries]

I suspect version 1 is just Vega 56 alongside a custom-SKU Xeon. Version 2 will probably be something more specialised- I'd expect a semicustom APU.

This is from https://stadia.dev/ Maybe it is still too early to have something which is really (semi-) custom...

 

[Asterox]

Because Intel is embarrassed...

Intel embarrassed or ashamed, no Intel does not know the red invisible nonsense.You probably remember 28 Core Xeon overclocking to 5ghz with Wather chiller.

Intel is first very greedy, or lowering CPU prices only if there is no other logical option.

 

[liahos1]

The other question is how much of an abstraction layer there is between the game and the hardware. Is google really locked to AMD GPUs in the future if this takes off?

If all they are promising is 4k60 and eventually 8k120, does the user really care what's running in the racks? Does Google?

 

[dacostafilipe]

The other question is how much of an abstraction layer there is between the game and the hardware. Is google really looked to AMD GPUs in the future if this takes off?

This has certainly something to do with AMD having open source drivers where nVidia does not.

 

[piesquared]

This has certainly something to do with AMD having open source drivers where nVidia does not.

For sure. AMD believes strongly in an open source methodology. They've proved it over and over, while nvidia is the exact opposite attempting to lock everyone and everything to an nvidia controlled universe. It's their culture, and those days are history. The fact that Vulkan is Mantle at the core is likely a decisive factor as well.

 

[amd6502]

It does make sense that the large number quoted for RAM is going to be the sum of DDR4 and HBM.

The numbers match Vega 56 (486mm2) or a cut down lower frequency Vega VII (331mm2). I think it's the latter because they can't run at such wattage. Vega VII gets 11 to 14 TFLOPs if clocked at 1400-1750 MHz: https://en.wikipedia.org/wiki/AMD_RX_Vega_series

But this would be using 300W, which is too much. So it's gotta be 7nm. Maybe even Navi. Either that or the google figure is a peak and not sustained figure for single precision FLOPs.

--edit: Revising my guess to mostly (~85%+) 7nm Vega with ~15% mix of 14nm Vega 56 for use during peak times. As for cpu, tuna's guess of old xeons seems most sensible and likely.

 

[majord]

If it's indeed MCM GPU CPU HBM2, then EBIM might hold the key to 'why Intel'

 

[beginner99]

So we can have 8GB of HBM2, and 8GB of DDR4. And there is up to 484GB/s if you're looking at the HBM2 block and not the DDR4 block. The usage of "up to" is actually pretty odd when listing bandwidth, but makes sense when you look at each node as having two separate memory pools. Not to mention, why list HBM2 under GPU header when there's a separate Memory section? That seems pretty telling. The only thing I can think of is because that HBM2 pool is only available to the GPU. It looks like a bit of marketing speak to make the thing look a bit more impressive than it really is.

Exactly my thought. The "up to" under memory bandwidth tells it all.

 

[Tuna-Fish]

Easy, they plan to ditch it for Zen 2 in the next iteration, therefore do not want to give it publicity. That would also explain AVX2 only as Zen won't support AVX-512 (therefore it's best to avoid it alltogether, or otherwise some devs might start using it and would need to undo it later)

I suspect version 1 is just Vega 56 alongside a custom-SKU Xeon. Version 2 will probably be something more specialised- I'd expect a semicustom APU.

Right now, google has a mountain of chips that are vulnerable to spectre&meltdown&spoiler&friends in their servers. Some of those are "custom" Xeons. I strongly feel that google is replacing all the vulnerable chips that are used in places where it matters with fixed ones as soon as they are available. This mountain of chips can then be put to use running Stadia.

They might start using Zen 2 if they run out of Xeons, but that would require much more demand than I expect Stadia to have. That might happen at some point in the future when the Xeons just get too old, but that's probably too far in the future for the deal to exist yet.

 

[jpiniero]

Right now, google has a mountain of chips that are vulnerable to spectre&meltdown&spoiler&friends in their servers. Some of those are "custom" Xeons. I strongly feel that google is replacing all the vulnerable chips that are used in places where it matters with fixed ones as soon as they are available. This mountain of chips can then be put to use running Stadia.

That was what I was implying, and why Intel didn't specifically get mentioned.

 

[Yotsugi]

It's a Cascade Lake Xeon.

 

[DrMrLordX]

It's a Cascade Lake Xeon.

Those are neither vulnerable to Spectre nor Meltdown. They're also relatively recent acquisitions. If that's true, then @Tuna-Fish 's assertion that Google is repurposing vulnerable Xeons (okay, Cascade Lake is vulnerable to Spoiler) may not be exactly correct.

 

[Schmide]

Those are neither vulnerable to Spectre nor Meltdown.

It is disingenuous to say they are neither vulnerable to Spectre nor Meltdown. It mitigates 2 variants (s2 m3) not the whole stack of compromising algorithms.

 

[TheELF]

Also how can they have a custom Intel CPU (as guessed by some) if Intel is not one of their partners.

The only type of CPUs they have are intel ones
https://cloud.google.com/compute/docs/cpu-platforms
The specs they give is just an equivalent,it's the virtual machine settings they will use on any of the servers they have,just like the virtual machines they rent out right now,look below .
https://cloud.google.com/compute/docs/machine-types
All the GPUs they use right now are nvidia but I guess they need to keep those for the industry so they will add the amd gpus to do the gaming.
https://cloud.google.com/compute/docs/gpus/

 

[DrMrLordX]

It is disingenuous to say they are neither vulnerable to Spectre nor Meltdown. It mitigates 2 variants (s2 m3) not the whole stack of compromising algorithms.

I was referring to this:

https://www.anandtech.com/show/1330...e-intel-clarifies-whiskey-lake-and-amber-lake

Yes, Cascade Lake isn't hardware-patched against Spectre 1 and Meltdown 3a and 4, but the worst ones performance-wise (Meltdown 3 and Spectre 2) are fixed in hardware. I don't think Google is going to be in a big hurry to replace Cascade Lake due to Spectre/Meltdown. Spoiler, on the other hand . . .

 

[Asterox]

The only type of CPUs they have are intel ones
https://cloud.google.com/compute/docs/cpu-platforms
The specs they give is just an equivalent,it's the virtual machine settings they will use on any of the servers they have,just like the virtual machines they rent out right now,look below .
https://cloud.google.com/compute/docs/machine-types
All the GPUs they use right now are nvidia but I guess they need to keep those for the industry so they will add the amd gpus to do the gaming.
https://cloud.google.com/compute/docs/gpus/

People is geting stuck on Hyperthreaded, but AMD SMT or Intel Hyperthreading the meaning is the same.

Google plays "background games vs Intel", or there is good reason why Intel is not mentioned anywhere.Google probably has some problem with "Intel business practice".Google is giant and it can do what they want, Intel it is no longer only choice(price performance ratio) or AMD Epyc or Epyc 2 are knocking on the doors.So "background games vs Intel" or Intel will not be on the Goodle Stadia posters, because Intel it did not deserve to be on posters.

 

[jpiniero]

Hyperthreading is an Intel trademark.

 

[TheELF]

Google plays "background games vs Intel", or there is good reason why Intel is not mentioned anywhere.Google probably has some problem with "Intel business practice".Google is giant and it can do what they want, Intel it is no longer only choice(price performance ratio) or AMD Epyc or Epyc 2 are knocking on the doors.So "background games vs Intel" or Intel will not be on the Goodle Stadia posters, because Intel it did not deserve to be on posters.

Sure they are going to throw away all the servers they have right now and spend all the money on not being able to get enough epyc units because AMD can't even produce as many as google would need.
Makes total sense.

 

[Hitman928]

Intel CPUs confirmed.

https://www.pcgamesn.com/stadia/google-stadia-release-date-price-performance

Google comment:

Yet these specs will adapt to the ebbs and flows of the gaming industry and the hardware available.

“We fully expect further iteration in our platform,” Phil Harrison says. “We’re just talking about Gen 1 at the moment, but there will be iterations on that technology over time.”

So the prediction that maybe 1st gen uses intel CPUs but Google is already planning on replacing them with AMD in future generations and that's why intel wasn't announced as a partner is certainly plausible. I don't know how far down the road Google has planned this thing though. Could be that they are just focusing on this gen and if it's successful they'll evaluate hardware options for a 2nd gen at that point in time.

 

[dacostafilipe]

Don't really care if it's AMD or Intel ... I'm more interested on the reason why they don't disclose the vendor

 

[Asterox]

Sure they are going to throw away all the servers they have right now and spend all the money on not being able to get enough epyc units because AMD can't even produce as many as google would need.
Makes total sense.

Of course not, after all nobody even thinks about throwing anything Intel into the trash.Again the same dilemma, Google Stadia posters where is Intel logo if Intel is CPU partner?

- Intel is CPU partner, not AMD?
- Intel is CPU partner, but only for a certain period of time or for Google no new Intel CPU servers?