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8P + 24D or 8P + 32D would be a lot more enticing.
Heck, even just 32D with V-cache could be pretty compelling.
32D with V-cache AND 32GB or 48GB LPDDR5X + RDNA4 = Apple M3 Pro competitor!
It’d absolutely work fine on a Zen 5 CPU that has both a normal CCD and a CCD with dense cores.Coding games, not playing them ^
The thing with Zen5c is that it's the same IPC core with less L3, and running at lower clock. E cores on the other hand are way weaker that P cores IPC wise, while having less cache and running at lower clocks. Zen5 hybrid chips would run MTed games much better than any Intel hybrid chip would.It’d absolutely work fine on a Zen 5 CPU that has both a normal CCD and a CCD with dense cores.
There’s a ton of games that utilize e-cores with great performance (The Last of Us & Jedi Survivor are recent ones). Both of those games have e-cores running tasks that aren’t latency critical (streaming assets, decompression, etc). For a modern multi threaded game each thread is given a priority and then handled by the scheduler appropriately.
That makes even less sense. You want much higher MT performance for game development, whether you're rendering, compiling, running multiple instances, etc. then you do for just playing games. And dev tasks (outside of some audio production workloads) are less likely to be latency sensitive.Coding games, not playing them ^
Depends entirely on how ST vs MT sensitive those lower priority tasks are. And for that matter, how Intel's E-cores vs AMD's dense cores evolve over time.The thing with Zen5c is that it's the same IPC core with less L3, and running at lower clock. E cores on the other hand are way weaker that P cores IPC wise, while having less cache and running at lower clocks. Zen5 hybrid chips would run MTed games much better than any Intel hybrid chip would.
I'm not making a claim that the Intel e-cores are more performant. I'm just saying that having a CCD with Zen 5C cores wouldn't wreck its ability to be a solid gaming CPU since there are games out right now that can take advantage of a heterogeneous CPU.The thing with Zen5c is that it's the same IPC core with less L3, and running at lower clock. E cores on the other hand are way weaker that P cores IPC wise, while having less cache and running at lower clocks. Zen5 hybrid chips would run MTed games much better than any Intel hybrid chip would.
If the 7950X3D has taught us anything, it's that allowing threads to stray onto the slower CCD makes the entire game slower. If there are 16-32 dense cores running at half the clocks (or worse) as the main CCD, the last thing you're gonna want is any game from 2023 mistakenly using that second CCD! Unless something major changes soon in how game engines work, I don't expect that situation to change much.Why would it close that door? There's nothing about gaming that demands the same performance on every thread, and there are even some games today that will make use of Intel's E-cores.
Huh? The 7950X3D performs sub-optimally when either the game's performance critical threads are split across multiple CCDs (die to die communication overhead), or the game is statically bound to the wrong CCD. Changing one die to dense cores doesn't impact that at all. You still want the game primarily bound to one CCD, and it's actually simpler as that one is clearly faster in ST under all circumstances.If the 7950X3D has taught us anything, it's that allowing threads to stray onto the slower CCD makes the entire game slower. If there are 16-32 dense cores running at half the clocks (or worse) as the main CCD, the last thing you're gonna want is any game from 2023 mistakenly using that second CCD! Unless something major changes soon in how game engines work, I don't expect that situation to change much.
The 13900k for example can not touch my 7950x's in productivity in what I do. Not to mention the 7950x can use avx-512 which I also use. You comment only applies to the types of applications that the hybrid approach works better on. NOT ALL PRODUCTIVITY APPS. Please keep your Intel specific comments in Intel threads.Huh? The 7950X3D performs sub-optimally when either the game's performance critical threads are split across multiple CCDs (die to die communication overhead), or the game is statically bound to the wrong CCD. Changing one die to dense cores doesn't impact that at all. You still want the game primarily bound to one CCD, and it's actually simpler as that one is clearly faster in ST under all circumstances.
And in practice, the issue you describe doesn't happen on Intel hybrid systems, despite being rather more complex. You don't see any game inexplicably running on E-cores, do you? No reason to believe AMD would have it worse.
Moreover, the top SKUs are not really for gaming. If you just want to game, get the 9800X3D or whatever and call it a day. The top SKUs are good for productivity, and E-peen, both of which will benefit from a hybrid approach.
There is nothing Intel-specific about what I wrote. I've shown you benchmarks before, and will not waste the time to repeat myself. Productivity apps make good use of hybrid, and there's no reason to believe that would not apply to an AMD hybrid offering.The 13900k for example can not touch my 7950x's in productivity in what I do. Not to mention the 7950x can use avx-512 which I also use. You comment only applies to the types of applications that the hybrid approach works better on. NOT ALL PRODUCTIVITY APPS. Please keep your Intel specific comments in Intel threads.
That's just a scheduling problem, and a more difficult one for the 7950X3D than for a theoretical hybrid chip at that. Having two CCDs which are both best at ST, just under different workload conditions, is much harder to deal with than knowing that one will always be faster. We see that in practice games never just get pinned to the E-cores on Intel hybrid chip, so I think Windows scheduling is already where it needs to be in that regard.Only it isn't just the game being statically bound to the wrong CCD, it can also be the OS allowing threads to wander between CCDs.
As mentioned, shouldn't be any worse than what we see today. If the OS allows a thread to wander, it would presumably be a perf-insensitive one. The hit from the other CCD seems to be more about the cross-CCD latency than clock speed. Might get a one or two games that need patching, but I doubt it'd be anything significant.If even a few threads wander to a high-density, low-clock CCD on a Zen5 desktop chip then performance could crater.
Yes, the top SKU usually puts out the top gaming numbers, but the difference is almost entirely clock speed, which can be normalized by overclocking, or AMD just making different SKU decisions. Either way, the gap is negligible vs a single CCD 8c chip. If you have a 4090 and money to burn, sure, go for it, but for your average gamer, even enthusiast, grab the 8c X3D and you'll never have to worry about it. Though I am assuming that AMD fixes the v-cache frequency penalty sooner or later.Traditionally they have been in the x86 market.
Is that not the current reality anyway? The 8c CCD boundary is a very similar problem to Intel's 8 P-core limitation. Long term, I'm sure game devs will find ways to use all that compute sitting idle. And when you think about it, density vs peak performance might be an appealing tradeoff for consoles...If AMD joins Intel in the box of "8c is enough" and instead encourages the proliferation of many slow cores in one form or another, then it's going to discourage a certain amount of innovation in that regard.
Since AMD has no hybrid chips, you must be talking about Intel. And with Bergamo, they have made it clear that they will NOT be going with a hybrid approach.There is nothing Intel-specific about what I wrote. I've shown you benchmarks before, and will not waste the time to repeat myself. Productivity apps make good use of hybrid, and there's no reason to believe that would not apply to an AMD hybrid offering.
But clearly you just wanted an excuse to go on your typical rant. I'd be shocked if you could go a single comment without mentioning your obsessive hatred of Intel.
They have not. And with Bergamo, they have made it clear that they will NOT be going with a hybrid approach.
lolAs far as my "hatred of Intel", thats not true.
AMD did, in fact, say that Bergamo was server only. They also did say they would not be taking the same approach as Intel. Neither of those statements rules out a hybrid approach, but the few serious rumors I have seen thus far indicate AMD is sticking with 8-16 cores on the desktop. They are even reusing the naming scheme.They have not
No one here is contesting that?AMD did, in fact, say that Bergamo was server only.
Yes.They also did say they would not be taking the same approach as Intel.
So what @Markfw said was false, and was exactly what I disagreed with. Nothing about Bergamo has shown that AMD is not going with a hybrid approach, does Intel's Sierra Forest prove that Intel isn't going with a hybrid approach with Arrow Lake then?Neither of those statements rules out a hybrid approach,
Why wait for Zen 5? Apparently Zen 4 mobile will have Zen 4C cores as well.Mobile? Potentially a different story. Mobile could very well be a monolithic hybrid design. 4-8 high frequency cores, 8-16 lower clocking small cores.
That igor leak for ARL makes it look like Zen 5 will be a good a 10-20% faster in ST and MTArrow Lake will be a huge step up for Intel in terms of perf/watt and will be an okay perf uplift, but Zen 5 will be faster thanks to a healthy IPC improvement.
All I said was "lol"Regarding your comments about @Markfw , uncalled for.
There's a difference between pessimism and outright fanboying, and I suspect many of here on Anandtech noticed Markfw cross that line... numerous times- in a repetitive fashion that has become recognizable as a pattern.Finally, sometimes folks here are super pessimistic about Intel’s ability to execute because they have over promised and under- delivered so many times. There is nothing wrong with that. Results are proven with actions, not words.
There's a difference between pessimism and outright fanboying, and I suspect many of here on Anandtech noticed Markfw cross that line... numerous times- in a repetitive fashion that has become recognizable as a pattern.
But, in respect to both Markfw and Anandtech's rules (as I very recently got a ban hammer for a day for cussing lol) I won't talk about his antics beyond this response for a bit.
How did you manage to bring Intel's outdated turbo tables into a Zen thread? The only frequency hardcoded in today's Zen chips should be the upper limit, everything else depends on cooling headroom.That's a decision made by AMD when establishing clockspeed and power targets for each CCD under specific utilization scenarios.
Is that not the current reality anyway? The 8c CCD boundary is a very similar problem to Intel's 8 P-core limitation. Long term, I'm sure game devs will find ways to use all that compute sitting idle. And when you think about it, density vs peak performance might be an appealing tradeoff for consoles...
How did you manage to bring Intel's outdated turbo tables into a Zen thread?
The only frequency hardcoded in today's Zen chips should be the upper limit, everything else depends on cooling headroom.
I think we are talking about different thing. The part you are talking about is essentially binning, of course different cores and different CCDs have different qualities. Of course they are set accordingly, you don't want processes to end up on weak cores or the weak CCD if better cores/CCD are available.Based on what we know from messing with PBO + Curve Optimizer, AMD has the capability to set whatever power/clockspeed target they want on a per-core or per-CCD basis. There's a lot of room for fine-grain control here. If AMD wanted to keep CCD0's clockspeed target high(er) when utilizing CCD1 then they could probably do so, at the cost of clocks on CCD1. Out-of-the-box they don't do so, and they still haven't offered a "gamer" mode where they attempt such behavior (instead, they let you just disable the second CCD). Again there's no free lunch, but they certainly have the controls available to shift power budget towards CCD0. Of course taking that behavior too far could lead to the same things I'm speculating could happen on future Zen5 products with a dense CCD: CCD1's clocks could become low enough that moving threads there would tank overall performance. In which case AMD might be better off raising power budget a bit for gaming workloads, but only for CCD0. As it stands, most 2 CCD Zen CPUs do not reach their full power budget when running games.
Nothing about Bergamo has shown that AMD is not going with a hybrid approach
AMD themselves call it hybrid, which I think is sufficient by itself. The scheduler doesn't care about the underlying RTL or physical design. Different means to the same end.Let's say they put Zen4 and Zen4c in an APU. Would it really be hybrid?
There are many benchmarks for games that run a lot better with E-cores off, WoW being a very prominent example. Frankly I've seen nothing good to be said by either vendor about their relationship with windows thread scheduling. I am not sure why you keep posting this rhetoric that there is some AMD scheduling problem when it literally crops up in Intel chips all the time too.We see that in practice games never just get pinned to the E-cores on Intel hybrid chip, so I think Windows scheduling is already where it needs to be in that regard.
That is certainly not what Raptor Lake benchmarks show.There are many benchmarks for games that run a lot better with E-cores off
Huh? I was explaining why hybrid would not be an issue for gaming, if AMD decides to go that direction. I think 8+16 would be the natural evolution for AMD's halo product.I am not sure why you keep posting this rhetoric that there is some AMD scheduling problem when it literally crops up in Intel chips all the time too.
