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Extraordinary claims require extraordinary evidence.... but I guess we could settle for just ordinary evidence, if you could care to provide some. Because, in i

Extraordinary claims require extraordinary evidence.... but I guess we could settle for just ordinary evidence, if you could care to provide some. Because, in its absence, what you wrote doesn't ring at all true.

sudosysgen 5y ago
How is this the case? AMD mobile CPUs, core for core, are anywhere from 13% slower to 20% faster (between Geekbench and Cinebench r20 and everything in between), and the M1 Max has a generational process advantage and 2-3x faster RAM, despite a similar TDP. In multicore, the Apple processors plainly consume way more power (62W vs 35W sustained) than any of the latest generation AMD processors yet released. Clearly the gap is within to ~25% process advantage and that's without taking into account much faster RAM. Same goes in phones. The A14 is around 10-20% faster in all metrics than an 888 and has around that much of a process advantage.
- wtallis 5y ago
  You seem to be comparing the nominal TDP of AMD chips against the actual measured power of Apple chips. It's really not safe to assume that a chip's advertised TDP is well-correlated with real power consumption for any particular workload; a sound comparison requires matched power and performance measurements. This is especially necessary when discussing benchmarks that have a short duration or are a variable workload, because a single TDP number cannot convey turbo behavior.
  - sudosysgen 5y ago
    I am not assuming that. The 5980HS actually consumes only 35W for sustained loads. It can boost up to 62W for 1-2 seconds and then drops to 42W and soon drops to 35W after a maximum of 5 minutes. The SPECInt suite lasts from 1000 to 3000 seconds. Therefore the 5980HS was at 35W for the vast majority of the test.
    - wtallis 5y ago
      > The SPECInt suite lasts from 1000 to 3000 seconds. Therefore the 5980HS was at 35W for the vast majority of the test. That cannot be presumed based solely on the nominal TDP and the total duration. SPECInt is a suite of a wide variety of sub-tests. It is not at all a consistent sustained test like the Prime95 results you are using as the basis for the turbo behavior. Actual power consumption during SPECInt is highly variable, because the workload itself is highly variable. Whether it truly averages out to 35W over the full duration is something that must be measured, not assumed. And you definitely cannot generalize your assumptions to apply to benchmarks or workloads with durations that are not far longer than the 5 minute turbo duration observed under Prime95.
      - sudosysgen 5y ago
        That's not how the turbo works on this AMD mobile chip. There is maximum time that the chip can sustain turbo and that is exactly 300 seconds. As long as the chip is in it's maximum p-state for the duration of the MT test, it will count towards that 300 second turbo time. Prime95 uses more ALUs, caches, and pipelines and thus hits the thermal limit faster and at the same power runs at a lower clock, but this isn't a thermal limit, it's a power limit. Indeed, we see the 300-second turbo limit not only on Prime95, but also on lighter, real-word tests like on an Agisoft DC workload.
        wtallis 5y ago
        I'm not contesting that the AMD chip in question (as typically configured by notebook OEMs) will not remain in turbo mode for more than 300 seconds at a time. What I'm pointing out is that you cannot assume that all workloads are steady enough over time to produce the simple sustained behavior illustrated with Prime95. This is especially inappropriate when you are referring to another test that directly contradicts this assumption and illustrates variable performance and power consumption, where power does not always stay at 35W even after the initial turbo period is over: https://images.anandtech.com/doci/16446/Power-Agi-5980HS-Perf.png https://images.anandtech.com/doci/16446/Power-Agi-5980HS-Per...
- deleted 5y ago
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sudosysgen 5y ago

How is this the case? AMD mobile CPUs, core for core, are anywhere from 13% slower to 20% faster (between Geekbench and Cinebench r20 and everything in between), and the M1 Max has a generational process advantage and 2-3x faster RAM, despite a similar TDP. In multicore, the Apple processors plainly consume way more power (62W vs 35W sustained) than any of the latest generation AMD processors yet released. Clearly the gap is within to ~25% process advantage and that's without taking into account much faster RAM. Same goes in phones. The A14 is around 10-20% faster in all metrics than an 888 and has around that much of a process advantage.

wtallis 5y ago
You seem to be comparing the nominal TDP of AMD chips against the actual measured power of Apple chips. It's really not safe to assume that a chip's advertised TDP is well-correlated with real power consumption for any particular workload; a sound comparison requires matched power and performance measurements. This is especially necessary when discussing benchmarks that have a short duration or are a variable workload, because a single TDP number cannot convey turbo behavior.
- sudosysgen 5y ago
  I am not assuming that. The 5980HS actually consumes only 35W for sustained loads. It can boost up to 62W for 1-2 seconds and then drops to 42W and soon drops to 35W after a maximum of 5 minutes. The SPECInt suite lasts from 1000 to 3000 seconds. Therefore the 5980HS was at 35W for the vast majority of the test.
  - wtallis 5y ago
    > The SPECInt suite lasts from 1000 to 3000 seconds. Therefore the 5980HS was at 35W for the vast majority of the test. That cannot be presumed based solely on the nominal TDP and the total duration. SPECInt is a suite of a wide variety of sub-tests. It is not at all a consistent sustained test like the Prime95 results you are using as the basis for the turbo behavior. Actual power consumption during SPECInt is highly variable, because the workload itself is highly variable. Whether it truly averages out to 35W over the full duration is something that must be measured, not assumed. And you definitely cannot generalize your assumptions to apply to benchmarks or workloads with durations that are not far longer than the 5 minute turbo duration observed under Prime95.
    - sudosysgen 5y ago
      That's not how the turbo works on this AMD mobile chip. There is maximum time that the chip can sustain turbo and that is exactly 300 seconds. As long as the chip is in it's maximum p-state for the duration of the MT test, it will count towards that 300 second turbo time. Prime95 uses more ALUs, caches, and pipelines and thus hits the thermal limit faster and at the same power runs at a lower clock, but this isn't a thermal limit, it's a power limit. Indeed, we see the 300-second turbo limit not only on Prime95, but also on lighter, real-word tests like on an Agisoft DC workload.
      - wtallis 5y ago
        I'm not contesting that the AMD chip in question (as typically configured by notebook OEMs) will not remain in turbo mode for more than 300 seconds at a time. What I'm pointing out is that you cannot assume that all workloads are steady enough over time to produce the simple sustained behavior illustrated with Prime95. This is especially inappropriate when you are referring to another test that directly contradicts this assumption and illustrates variable performance and power consumption, where power does not always stay at 35W even after the initial turbo period is over: https://images.anandtech.com/doci/16446/Power-Agi-5980HS-Perf.png https://images.anandtech.com/doci/16446/Power-Agi-5980HS-Per...
deleted 5y ago
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