Ran into this exact thing on my ThinkCentre. Every tool I tried (Task Manager, HWiNFO, even Lenovo Vantage) reported the fan at 0 RPM while it was obviously spinning, because Windows only ever sees a stubbed-out embedded controller. I ended up reverse-engineering the real EC and writing a small open-source tool that reads the actual RPM, shows per-core CPU temps, and switches the fan modes, including a Full Speed mode that's normally locked away in the BIOS.
Honest on scope: I've only verified it on my M70t Gen 6, so on other boards it runs monitoring-only until the EC layout gets mapped, and readings can be off. If it doesn't work for your model, please open an issue on the repo with your model and baseboard number and I'll definitely add it.
MIT, no telemetry: https://github.com/blazingphoenix7/thinkcentre-fan-control
