Could be a faulty fan.
Happened to my X230 previously. Fan will spin ok during boot up but when the CPU heats up, it slowed down. Tried oiling it but no avail. Ended replacing it with a new fan from AliExpress. Works well since.
[WTA] Root cause for Thermal Throttling, Laptop CPU Overheat
Nov 16 2024, 08:32 AM
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