Try other Headers on your motherboard or call the support for halp if there is a problem with your board. Look into the Bios! Do it say more than "error"? Is one of your Header shorted?
I have a Z170-A MBO, in a Phanteks luxe case, and a twin fan phanteks CPU cooler
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twin cpu fans join and connect to fan4 header on the MBO
The case fan controller is connected to the CPU_fan header on the MBO
The 3 case fans individually connect the case controller
the controller also have a 12v supply.
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I am getting a CPU fan speed error detected message on start up.
have i connected something up wrong? Please help as i have spent hours trying to figure out why i am getting the error