How can I tell if the CPU fan header on the motherboard is working?

buddyeckles

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Nov 28, 2004
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I have a Gigabyte G1.SNIPER Z97 motherboard in a new build. When I turn it on (without monitor or input devices) the CPU heatsink/fan does not run. Replaced with new heatsink/fan, no obstructions, but new fan does not work. How can I check the CPU fan header to see if it's working?