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by ceratopisan 2847 days ago
You are confusing principle with implementation. Reducing clock speed reduces power usage and you can compensate with more cores is indeed a truth. However, finding that option in consumer hardware has been relatively difficult. That is the surprise indicated.
2 comments

Ryzen is known to be memory constrained even with much faster memory than he used. It is completely predicable that he found his CPU to be severely starved for memory bandwidth thus enabling him to reduce operating frequency without penalty.

This is like putting an LS engine in an otherwise stock Miata and acting surprised that you can run the engine at lower RPM and still put in good lap times.

Are you kidding me? That's only true if the constraint can be removed in a hardware upgrade. Apparently latter day Xeons are not much better at hiding memory latencies than Zen and no longer outrun it as much like they did Bulldozer on other operations which made the latencies irrelevant.

In other words, he's reached peak CPU. As in a faster unit will not speed it up, and more cores can only do that to a point. Amdahl law (power efficiency variant) and also memory controllers say hello.

Note that the author is not claiming that he compensated with more cores. He is claiming that the performance is roughly the same, at the same core count (8), regardless of frequency.