I guess they doubled the ALUs and not worried about feeding them fully since they are limited by other things anyways, like bandwidth or power? Maybe they can be used for specific things in RT. Probably doesn't cost that much area to just add them if they don't add too much extra silicon to try to feed them.
Nvidia Ampere Discussion [2020-05-14]
- Thread starter Man from Atlantis
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Just keep in mind it's likely beating the 2080ti in RT-limited games, not necessarily across the board. Even if it just comes fairly close in standard FP32, it's still a nice deal though.I'm excited. 3070 beating 2080Ti at a cost of 500. This makes sense. PC gaming is saved
Maybe that's a hint of good competition as well...
D
Deleted member 2197
Guest
Is it? I thought it was also from a non RT game perspective.
Impressive, the 3080 is stronger than I had thought it would be. Did a better job of hyping me than the presentation itself.
Check out the DF video, the 3080 absolutely crushes the 2080 by 70% or more in non RT games. Don't underestimate the 3070 in non RT games, either.
Benetanegia
Regular
I don't really think it's just bandwidth, etc. I still believe in what was discussed here before when 2xFP rumours arised, that it can either do either 1 FP+1 INT like Turing does or 2xFP per clock. Since according to Nvidia (on Turing presentation) games on average do 36 INT ops per 100 FP ops, Turing would do on average 136 ops per 200 "cycles" despite being in theory capable of 200. Gaming Ampere does 200 regardless of FP/INT mix. And if you do the math 200/136 = 1.47, so about 50% faster SM on average though it probably varies wildly on game basis.
Sure that's the thing. I have no idea how much an extra 16xFP32 SIMD would add, but even a 20% SM size increase for a 50% perf boost is pretty good. Tho the question that I've had since the rumours about 2xFP arised is why they didn't do it for Turing, when it makes much more sense. I mean they actually had the numbers.
Man from Atlantis
Veteran
RT performance delta vs non RT delta is not that different as youd expect though ~85% to ~70% respectively 3080 vs 2080.
Benetanegia
Regular
Also optimization is a thing guys and games haven't been retroactively optimized for Ampere.
Just remember to temper your expectations about game startup times when you switch hardware and upgrade video drivers frequently, as is typical of new products, 
https://forum.beyond3d.com/threads/...pc-about-to-become-a-bigger-bottleneck.61929/
https://forum.beyond3d.com/threads/...pc-about-to-become-a-bigger-bottleneck.61929/
Well this is their slide
Since we have no breakdown or numbers yet, I think it's safe to assume that "multiple popular graphics intensive games" includes a mix of RT and non-RT titles, which means as an average it's probably winning in RT and losing in pure FP32.
The 3080 has a fairly significant bandwidth difference whereas the 3070 might be rather starved for bandwidth compared to the 2080ti.
As always, just trying to temper expectations vs marketing
Example, their 3070 page has this graph and BL3 compared to a 2080ti which can push 90fps easily at 1440p. But for $500? Yeah, there's going to be some cheap 2080ti's on the market soon...
Well that Borderlands 3 chart confirms my suspicion. There's actual no IPC increase from Turing SM, just more cores, more bandwidth and possible higher boost clock doing the magic. The other FP32 ALUs help with Raytracing.
If AMD had product on the market that would be an upgrade from the 2080 Ti I just sold, I would gladly consider it. That's highly unlikely, though. Also I have a Gsync display.
Huh? "IPC" with GPUs doesnt make sense without more units. They are throughput processors. More cores, more throughput, more performance.
D
Deleted member 2197
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Perhaps, but that's usually the case with any new architecture. As long as your willing to forego all the "new" features that a new architecture brings I guess you should be fine.
Benetanegia
Regular
What? How can a 60% increase in perf (roughly 50 to 80) for a 27% increase in SM count at same clocks in any way confirm no IPC gain?
Let's wait for the real boost clocks to account for actual IPC increase. It certainly would explain the higher power consumption vs. RTX 2070. I just don't think the Ampere CUDA is such a huge jump from Turing as Nvidia wants us to believe. Just more of it. Nothing wrong with that per se.