[kllrnohj]

> The Ryzen setup has 3x the power envelope (in watts) as the M2[1]

TDP does not represent the power envelope of the chips. It's the sustained load target at best, but mostly even that is kinda made up and the rules don't matter. But for any short (where short is less than a minute or even 5 minutes) burst, that TDP figure is completely irrelevant. Nothing respects it. Also for single threaded tasks, neither one is even going to pull that high.

You have to compare actual power used during the specific test in question to make any such comparison. Otherwise trying to judge power consumption by looking at TDP is like trying to judge performance by only looking at clock speeds. Within the same manufacturers same generation you can kinda infer something useful. Other than that? Not a chance.

[neogodless]

https://www.phoronix.com/review/ryzen7-6850u-acpi/6

It's also interesting that the maximum power consumption eked out of the Ryzen 7 Pro 6850U was a touch under 32W. Where did this 46W number of the parent comment come from? Or the 50-60W in the comment below? They must be thinking of a different CPU/APU.

[Macha]

For a lot of Mac users, x86 = Skylake, as featured in the last Intel MacBook pro, and a lack of realisation that x86 has moved on.

[KingOfCoders]

Not only that, but the MacBooks with the very bad heat management (I've owned some I couldn't keep on my lap, also see Linus and Louis videos).

[Retric]

For small differences in TDP you kind of have a point, but 3x is relevant far more quickly.

[kllrnohj]

But again it's not. TDP isn't a defined thing. There's no standard for it. It's literally a made up value by the SoC manufacturer, and in the case of laptops the laptop manufacturer even gets to fiddle with it.

That said in this case it is a small difference regardless. The 6850U's TDP per AMD's spec is 15W-28W. That's bang on the same as M2 basically. There's no 3x difference here. Unless there is because again TDP is a made up number with no formal definition.

[Retric]

I had assumed it was 3x simply because you didn't object to their figure.

This laptop actually uses 28W TDP, so TDP is 2x not 3x which is still significant in less than 60 seconds.

[hajile]

M1/M2 use around 20-22w MAX in CPU-only tests. AMD and Intel chips usually max out at around 50-60w real-world power.

That's hardly apples to apples..

[kllrnohj]

> AMD and Intel chips usually max out at around 50-60w real-world power.

That's a sweepingly broad claim that's not at all well supported. AMD & Intel both make CPUs that top out far below 50-60w real-world power and also top out far, far above 50-60W real-world power.

From a different review of the same CPU (didn't check if same laptop, could be though) "The Ryzen 7 PRO 6850U with the Linux 5.18 kernel had a 18.4 Watt average (or 16.6 Watt average with Linux 5.19 Git) while the Ryzen 7 PRO 5850U average on Linux 5.18 was up at 21.96 Watts." https://www.phoronix.com/review/amd-ryzen7-6850u/8

So no, this isn't a 50-60W real-world power CPU. That's the non-U SKUs.

But if this AMD was a 50-60W CPU that'd exactly prove my point that TDP is a stupid number to compare and you always, always have to look at actual power consumption used (which this M2 vs. 6850U didn't do because as noted briefly in the intro power monitoring of the M2 doesn't work on Asahi yet)

[hajile]

Here's the 4800U running in a tiny NUC at over 60w and the 5800U running at almost 52w. They absolutely DO hit very high real power usage.

TSMC N5 only offers 15% performance OR 30% lower power vs 7nm. Peak clocks on the 6850U are 10% higher than the 5xxx generation AND is on N6 instead of N5 which offers a significantly lower advantage than what I stated. N6 offers an 18% reduction in area vs N7 while N5 offers a 45% reduction in area, so you can do your math from there.

https://www.anandtech.com/show/16236/asrock-4x4-box4800u-ren...

https://www.notebookcheck.net/R7-5800U-vs-E-2186M-vs-R7-PRO-...

[kllrnohj]

Why are you using peek instead of average? The average power over the test is what matters, not the instantaneous spikes. And did you miss the whole "configurable TDP" thing? The OEM gets to change the power targets. They aren't fixed. Saying the 4800U in a NUC uses power X, therefore all 4800U's use power X is flat out wrong. That's not how it works, different usages will set different power limits.