> The new Intel Clearwater Forest Xeon processors use Darkmont cores, which have approximately the same performance per core, the same die area per core and the same power consumption per core as the Neoverse V3
In no world will Darkmont perform like Neoverse V3 / Cortex-X4. Darkmont is much slower.
SPECint2017
Darkmont @ 3.5 GHz boost = 7.13 points
Cortex-X4 @ 3.2 GHz = 8.20 points (+15% faster)
Source: David Huang, https://blog.hjc.im/spec-cpu-2017
Arm's Neoverse V3 136-core CPU has a 3.2 GHz base clock, so the exact same as this Cortex-X4. Your real problem arises when a 288C Clearwater Forest CPU at the highest 500W TDP means a maximum of 1.7W per core (generous, as we're excluding uncore, fabric, cache, etc.). It's probably closer to 1.5W, but let's be generous and toss in +200mW.
Darkmont will be *nowhere* near 3.5 GHz at a mere 1.7W / core power budget. It'll be much closer to 2 GHz. Sierra Forest (6780E) is 144 cores @ 350W (2.2W / core) → a pitiful 2.2 GHz base clock. Let's go crazy and assume Darkmont magically achieves +13% higher clocks (2.2 → 2.5 GHz) at 22% less power (2.2W per core → 1.7W per core) and much higher IPC.
Darkmont @ hypothetical 2.5 GHz = ~5.09 points
Neoverse-V3 @ 3.2 GHz would be 61% faster.
>The only way how the claim of Arm can be true is if they have compared their new CPUs with antiquated CPUs like the Intel Granite Rapids Xeon CPUs, instead of comparing with state-of-the-art Intel Clearwater Forest and AMD Zen 5.
Intel had a paper announcement of Clearwater Forest this month. They have not revealed SKUs: no clocks, no model numbers, nothing exists. Nobody—including Arm—will be benchmarking against a CPU that doesn't exist on the market yet.