AMD: Navi Speculation, Rumours and Discussion [2019-2020]

You think the console cpus would really draw 50W? That means 150W x 2 = 300W for the GPU. Add in 40-50W for a PCB and you're now at 350W. If it's a 150W APU, that puts you at 100W x 2 = 200W + 50W for 250W total. Somewhere in the middle is probably a more realistic guess, which is around 300W.

 

PS5 Power supply is 350W. Xbox Series X less than that. With this wattage, they are designed designed to power: APU, memory, VRMs, fans, 2 NVME SSD, sound, other control circuitry on the MB, and all the USB ports it has, up to their max wattage and probably other stuff I forgot.

 

- "Higher-end Silicon" 6900XT: 2100MHz Game Clock - 2300MHz Boost Clock
- 3 GPUs being shown: 6900XT, 6800XT, 6800
- 6900XT has 80CUs.
- 6700 only launches in 2021
- RTX 30 is faster at raytracing


I really wanted the highest-end SKU as I haven't updated my GPU in over 3 years, but I think the 6900XT is coming in at 1000€ or more that's way more than what I'd consider paying for a GPU.

The worst case scenario is unrealistic, the best case isn't. Most probable outcome is in the middle, yes.

 

I think 250W for 2100MHz is pretty unlikely. I hope I'm proven wrong, but just strict doubling of a 5700 is going to be close to that @1655 MHz game clock, unless they've exceeded their 50% performance per watt goal. Usually those performance per watt figures are taken in the most favourable comparisons.

Honestly, looking at everything now if the benchmarks they showed at the ryzen event were the 72CU GPU that puts it in line with the 3080 and the 80CU will be pretty much in line with the 3090. Power numbers are looking not too much different either. I'm gonna bet they're within 30W of each other, which is not a big deal. I'm really curious to see how big navi performs at 1080 and 1440p though. Hoping the cache and VRAM are capable of feeding 128 rops (if it has that many) to push those lower resolutions a little harder. Ray tracing will also be interesting. I want RT for single player, but I want 1440p240 for online games.

 

Its a 350 watt psu for PS5 and 340 watt PSU for PS5 All Digital. I think it has more than 200 watts power budget for the APU.

 

That's 150 watts for GPU, memory, power delivery, fans and disc drive. Why would a PCB require 40 - 50w alone?

And 2x multiplication would give you 104CUs with 640bit bus.

 

PS4 Pro had a 310W power supply and it never did come even close to that budget.

 

They were originally targeting the RTX 2080 Ti. With the release of the RTX 3080 and the performance and the higher power that it has AMD probably needed to so the same to compete. Thus the higher clocks and power.

 

Not by much though. I'd expect it to be around 250W maximum with a 340-350W PSU.

 

There's guard-banding for eventual degradation in PSU performance, possibly safety margin for unpredicted power consumption spikes, and trying to keep consumption somewhere in the PSU's most efficient range.

Some elements like modern power management could potentially remove some of the guard-banding for safety and shift it to actual consumption, which might make the upcoming generation a less certain reference point.

The 2.23 GHz GPU is presumably operating past the inflection point where the power consumption curve gets noticeably hockey-stick like. Per the presentation on the PS5, a reduction of several percent yields ~10% power reduction, which is definitely past the sweet spot. I'd say this is focused on the GPU, since the CPU speeds are not close to that region for Zen 2.
There's also smart-shift, so taking a static cut from the power budget for the CPU isn't a safe assumption. Given where the GPU is being driven in terms of clocks, it's possible that it can consume much more of that budget on its own than prior generations might indicate.

Then there's the question of whether console makers are more thorough in setting low voltages versus yield, since a decent chunk of AMD's power consumption malaise has come from what seems to be a fair amount of extra voltage being applied to all chips than may be necessary.

 

I can't believe that. I mean why targeting an "old" gen, where ampere was around the corner ?

 

PS5 has 36 active CUs ... Doubling it is 72CU, which is what is expected for one of the two big navi variants. There will be a 72CU and an 80CU.

Edit: Also PC gpus tend to be in the 30-50W range for PCB, including fans, from my understanding.

 

It's possible that they haven't expected the doubling of FP32 units in Ampere.

 

XSX power consumption is already know... Despite it having a 310W PSU, its power usage is about 210W while running Gears 5. That is for everything, meaning RAM, CPU/GPU, SSD and so on. Other games use a lot less power.



If you shove off 50W for all the additional components (as an educated guess), you're left with ~160W for a 52CU RDNA2 GPU at 1.8GHz.

 

This is utter nonsense

 

Thats still without portions of the GPU being utilized, like the RTRT hardware. Its entirely unknown how that may have an impact.

 

We only have actual consumption figures for the Xbox series X. Let's also not forget the ps5 has a 256bit bus, 16gb gddr6. So doubling the CUs alone isn't going to linearly increase the power consumption

 

Gears 5 on XBSX includes RT elements

 

I think its SSGI (Screen Space Global Illumination) and not RealTimeRayTracing...

 

as per Richard:
It has a screen space ray traced GI solution but it is not hardware accelerated