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Comment by plasticchris | Hacker News Reader

TDP is arbitrary, they actually calculate it with arbitrary constants that change per chip. So it is meaningless at this point.

See https://gamersnexus.net/guides/3525-amd-ryzen-tdp-explained-...

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Also, chiplet based Ryzens are notorious for higher idle power consumption than Intel's monolithic dies, which is where CPUs spend most of their time in consumer applications (web browsing, netflix, shitposting on reddit, etc) instead of running at full load all the time.

Synthetic tests that stress everything at full bore, are not realistic representations for your average consumer PC application scenario. Even video games don't cause as much power draw as synthetic benchmarks can which are more akin to power viruses.

In real life daily driving, Ryzen might still be more efficient than Intels but with a much smaller margin than such tests might lead you to believe.

I'm currently typing this on an i7-1165G7 running windows 11, with a few background tabs in edge, teams and outlook. CPU usage as reported by task manager seems to hover around 7-10%. CPU clock hovers around 2.2 GHz with regular peaks above 3 GHz.

Is that idle? Not sure I could get this box at any lower use than this, even though I understand this is different from having all cores pegged at 100%.

Doesn’t idle mean something more like C:\> than multitasking billions of instructions per second?

We're talking idling from the perspective of an actual user at home, so there will obviously be a web browser and some background tasks running.

Idling without anything running, even an OS, is interesting for metrics, but not something realistic for any user.

I agree that we should be comparing real scenarios, but I also notice that my desktop Linux systems tend to idle at <=1% CPU use if I don't have a browser open, so there's probably some genuine room to consider what counts as idle even with an OS running.

Reporting the clock frequency of a core requires running a bit of code on it which necessarily means the core is in an active state while you take the reading, so you will always read something like "2.5 GHz" even if the core does not execute anywhere near 2.5 billion cycles while you do that. Some tools can report metrics like "average effective clock" which count time spent in inactive power states as zero clock.

Hwinfo64 can tell you the percentage of time the cpu speeds in the idle state.

Every Ryzen with letter G at the end is a monolithic design...

Interesting I didn't know.

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