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AMD's Strix Point: Zen 5 Hits Mobile

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Re: AMD's Strix Point: Zen 5 Hits Mobile

#111

Post by moffkalast »

hajile wrote: post #44
apatheticonion wrote: post #29

Are there any mini PCs with Zen 5?

I think there's a lot of hope for a Strix Halo mini-PC. We currently have 7840HS+6650M with two massive heatsinks just barely coming in at what you would consider a large mini-PC rather than a SFFPC. Just one chip cuts the heatsink demand in half. The cores should be faster and it moves from 28CU up to 40CU and from RDNA2 to RDNA3.5. As long as the cross-core-complex latency isn't as bad as the HX370, I think it coul…

Hell I'd settle for a Z1 SBC or even mini PC. They can't seem to keep up with demand for these new chips to put them into any sort of products that don't have complete mass appeal. It's impossible to find one that's not in a handheld gaming console. I doubt they'll even make enough of the Halo to cover laptops.

Re: AMD's Strix Point: Zen 5 Hits Mobile

#112

Post by fulafel »

rafaelmn wrote: post #76
kevin_thibedeau wrote: post #72

Earlier quoted context omitted.

Stop demanding paper thin laptops. My work Dell rarely turns on its fan unless an AV scan is in progress and even then it's rather tolerable. It isn't a fashionable thickness so has plenty of internal volume for heat distribution.

MacBook Air is thin and fanless, so it can be done.

Many things can be done if you don't have coexist with AV.

(Though the use of the fan is always a configuration choice with thermal management in CPUs these days).

Re: AMD's Strix Point: Zen 5 Hits Mobile

#113

Post by tuna74 »

kevin_thibedeau wrote: post #72
jml7c5 wrote: post #56

I sit firm in my belief that the best thing Microsoft could do for their laptop ecosystem is to add support for a "max fan speed" slider somewhere prominent in the Windows UI. People want the option to make their laptop silent or nearly silent. And when users do need the power, they generally prefer a slightly slower laptop at a reasonable volume rather than the roar of a jet engine. Laptop manufacturers want their d…

Stop demanding paper thin laptops. My work Dell rarely turns on its fan unless an AV scan is in progress and even then it's rather tolerable. It isn't a fashionable thickness so has plenty of internal volume for heat distribution.

I want a thin and fanless laptop. You might want something else.

Re: AMD's Strix Point: Zen 5 Hits Mobile

#114

Post by camel-cdr »

janwas wrote: post #108
dzaima wrote: post #106

Earlier quoted context omitted.

How does avl affect register renaming? (there's the edge-case of vl=0 that is horrifically stupid (which is by itself a mistake for which I have seen no justification but whatever) but that's probably not what you're thinking of?) Agnostic mode makes it pretty simple for hardware to do whatever it wants. Over masks it has the benefit of allowing simple hardware short-circuiting, though I'd imagine it'd be cheap enoug…

Was thinking of a shorter avl producing partial results merged into another reg. Something like a += b; a[0] += c[0]. Without avl we'd just have a write-after-write, but with it, we now have an additional input, and whether this happens depends on global state (VL). Espasa discusses this around 6:45 of https://www.youtube.com/watch?v=WzID6kk8RNs . Agree agnostic would help, but the machine also has to handle SW askin…

> Agree agnostic would help, but the machine also has to handle SW asking for mask/tail unchanged, right?

Yes, but it should rarely do so.

The problem is that because of the vl=0 case you always have a dependency on avl. I think the motivavtion for the vl=0 case was that any serious ooo implementation will need to predict vl/vtype anyways, so there might as well be this nice to have feature.

IMO they should've only supported ta,mu. I think the only usecase for ma, is when you need to avoid exceptions. And while tu is usefull, e.g. summing am array, it could be handled differently. E.g. once vl<vlmax you write the summ to a difgerent vector and do two reductions (or rather two diffetent vectors given the avl to vl rules).

Re: AMD's Strix Point: Zen 5 Hits Mobile

#115

Post by camel-cdr »

janwas wrote: post #100
hajile wrote: post #73

Earlier quoted context omitted.

I think you may be correct about gracemont v golden cove. Rumors/insiders say that Intel has supposedly decided to kill off either the P or E-core team, so I'd guess that the P-core team is getting layed off because the E-core IPC is basically the same, but the E-core is massively more efficient. Even if the P-core wins, I'd expect them to adopt the 3x3 decoder just as AMD adopted a 2x4 decoder for zen5. Using a non-…

> it's a matter of the wrong configuration unlike x86 where it is a matter of the wrong instruction +1 to dzaima's mention of vrgather. The lack of fixed-pattern shuffle instructions in RVV is absolutely a wrong-instruction issue. I agree with your point that multiple code variants + runtime dispatch are helpful. We do this with Highway in particular for x86. Users only write code once with portable intrinsics, and t…

> +1 to dzaima's mention of vrgather. The lack of fixed-pattern shuffle instructions in RVV is absolutely a wrong-instruction issue.

What others would you want? Something like vzip1/2 would make sense, but that isn't much of an permutation, since the input elements are exctly next to the output elements.

Re: AMD's Strix Point: Zen 5 Hits Mobile

#117

Post by AnthonyMouse »

aurareturn wrote: post #97
AnthonyMouse wrote: post #88

Earlier quoted context omitted.

> 1. ARM is inherently more efficient than x86 CPUs in most tasks > 2. Nuvia and Apple are better CPU designers than AMD and Intel The third possibility is that they just pick a different point on the efficiency curve. You can double power consumption in exchange for a few percent higher performance, double it again for an even smaller increase. The max turbo on the i9 14900KS is 253 W. The power efficiency is bad .…

>The third possibility is that they just pick a different point on the efficiency curve. You can double power consumption in exchange for a few percent higher performance, double it again for an even smaller increase. This only makes sense if the Zen5 is actually faster in ST than the M3. In this case, the M3 is 1.24x faster and 3.4x more efficient in ST than Zen5. AMD's Zen5 chip is just straight up slower in any cu…

> This only makes sense if the Zen5 is actually faster in ST than the M3. In this case, the M3 is 1.24x faster and 3.4x more efficient in ST than Zen5.

It makes sense if Zen5 is faster in MT, since that's when the CPUs will be power limited, and it is. For ST the performance generally isn't power-limited for either of them and then the M3 is on a newer process node.

It also depends on the benchmark. For example, Zen5 is faster in ST on Cinebench R23. It's not obvious what's going on with R24, but it's a difference in the code rather than the hardware.

The power numbers in that link also don't inspire a lot of confidence. They have two systems with the same CPU but one of them uses 119.3W and the other one uses 46.7W? Plausibly the OEMs could have configured them differently but that kind of throws out the entire premise of using the comparison to measure the efficiency of the CPUs. The number doesn't mean anything if the power consumption is being set as a configuration parameter by the OEM and the number of watts going to the display or a discrete GPU are an uncontrolled hidden variable.

> It's not a trade off that Intel wants.

It's the one they've always taken, even when they were unquestionably in the lead. They were selling up to 150W desktop processors in 2008, because people buy them, because they're faster.

Now they have to do it just to be competitive because their process isn't as good, but the process is a different thing than the ISA or the design of the CPU.

Re: AMD's Strix Point: Zen 5 Hits Mobile

#118

Post by moonfern »

sm_1024 wrote: post #57
hajile wrote: post #48

Earlier quoted context omitted.

Let's do the math on M1 Pro (10-core, N5, 2021) vs HX370 (12-core, N4P, 2024). Firestorm without L3 is 2.281mm2. Icestorm is 0.59mm2. M1 Pro has 8P+2E for a total of 19.428mm2 of cores included. Zen4 without L3 is 3.84mm2. Zen4c reduces that down to 2.48mm2. Zen5 CCD is pretty much the same size as Zen4 (though with 27% more transistors), so core size should be similar. AMD has also stated that Zen5c has a similar sh…

119W for hx370 looks extremely sus, seems to me more like the system level power consumption and not CPU-only. According to phoronix [1,2], in their blender CPU test, they measured a peak of 33W. Here max power numbers from some other tests that I know are multi-threaded: -- Linux 6.8 Compilation: 33.13 W LLVM Compilation: 33.25 W -- If I plug in 33W into your equation, that would give us score of HX 370: 104 PPA Thi…

About cinebench-geekbench-spec: https://old.reddit.com/r/hardware/comments/pitid6/eli5_why_d... That's about Cinebench 20, an overview of Cinebench 24 cpu&gpu(!): https://www.cgdirector.com/cinebench-2024-scores/

Re: AMD's Strix Point: Zen 5 Hits Mobile

#119

Post by AnthonyMouse »

rafaelmn wrote: post #76
kevin_thibedeau wrote: post #72

Earlier quoted context omitted.

Stop demanding paper thin laptops. My work Dell rarely turns on its fan unless an AV scan is in progress and even then it's rather tolerable. It isn't a fashionable thickness so has plenty of internal volume for heat distribution.

MacBook Air is thin and fanless, so it can be done.

"Thin and fanless" aren't that hard, just use any low power CPU.

But then people also want fast.

Apple does this by buying out TSMC's capacity for the latest process nodes and then taking the performance/efficiency trade off in favor of efficiency, so they get something with similar performance and lower power consumption. But then they charge you $400 for $50 worth of RAM and solder it so you can't upgrade it yourself.

The thing to realize is that fans are not required to spin, and the difference between the faster and slower processors are the clock speed rather than the transistors. So what you want is exactly what the OP requested: A laptop with fans in it, but you can turn them off. Then the CPU gets capped at a 15W TDP, has basically the same single-thread performance but is slower on threaded workloads, and it's no longer possible for Chrome to make your laptop loud.

But if you want to open up Blender you still have the option to move up the fan slider and make it go faster.

Re: AMD's Strix Point: Zen 5 Hits Mobile

#120

Post by thecompilr »

AnthonyMouse wrote: post #119
rafaelmn wrote: post #76

Earlier quoted context omitted.

MacBook Air is thin and fanless, so it can be done.

"Thin and fanless" aren't that hard, just use any low power CPU. But then people also want fast. Apple does this by buying out TSMC's capacity for the latest process nodes and then taking the performance/efficiency trade off in favor of efficiency, so they get something with similar performance and lower power consumption. But then they charge you $400 for $50 worth of RAM and solder it so you can't upgrade it yourse…

The M1 was made on 5nm which have long been available to AMD and other competitors in volume.
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