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Comment by loser777 | Hacker News Reader

I'm genuinely curious of the details of how the 1.5v vCore measurement was obtained. CPU-Z and software measurements in general don't have the greatest reputation of being accurate, especially with just-released generations of CPUs. Conventional wisdom has been with newer manufacturing processes, less voltage is required (and tolerated), and 1.5v vCore sounds truly insane in 2022 for a "4nm" chip. For reference, I haven't heard of 1.5v being a safe "24/7" voltage since the days of 90nm-130nm+ CPUs circa 2005-2006. IIRC casual overclockers in the forums weren't really comfortable with 1.5v even with 65nm Core 2, and this was back when it was common to e.g., safely overclock your 2.4 GHz Core 2 Quad to 3.4 GHz.

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1.5V was the normal operating voltage of the 130nm "Northwood" Pentium 4s. For 65nm processors it's usually around 1.3-1.4. The problem with high voltages is that while the CPU may appear to work fine for a while, it may start becoming unstable and then suddenly die.

Part of me wonders whether the CPU manufacturers decided to, after a very long period of being conservative with lifetime and seeing their products last too long to their liking combined with the diminishing increases in performance with each new model, go all-out with voltages that are guaranteed to cause failure as long as they could make almost all of them happen just outside of warranty; not unlike what the LED lighting market has done.

Probably used same registers as previous.

Would be simple to confirm with some scope probing CPU power.

The problem is the CPU itself isn't the one measuring voltage, it gets that information from the motherboard's VRM controller. The accuracy of the reported value can vary depending on the controller, how it's configured by the motherboard's firmware, and the physical circuit design.

That being said, with new motherboards generally using fully digital VRM controllers the reported value should be pretty close in most cases.

AMD has worked to make sure that everything lines up for this release with the tools people use. Their Ryzen Master (pretty good tool for tweaking ryzen settings) got a bit of a rework for zen4 as well.

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