u/Ateretu

MSI X870 Tomahawk CPU_FAN 1 dead?

Hi, I’ve had this motherboard for almost a year now and everything has been working perfectly.

​Today, while using my PC, I noticed that my CPU fan wasn't spinning. I plugged the fan into the SYS_FAN2 header, and it started working normally again. Should I return the motherboard under warranty?

​I’ve already tried resetting the BIOS, clearing the CMOS, forcing PWM mode in the BIOS, using auto-detect, and adjusting the fan curves, but nothing helped. My BIOS version is 7E51v1A67 (from August 2025)

​My specs:

​CPU: AMD Ryzen 7 9700X

​Cooler: BeQuiet Dark Rock Pro 4

​Case: BeQuiet Dark Base Pro 900 rev2

​PSU: Corsair RM750x

​GPU: AMD Radeon RX 9070 XT

​Could a BIOS update potentially fix this? Or is the CPU_FAN header completely dead, leaving a warranty as my only option?

​Thanks for the help!

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u/Ateretu — 5 days ago