Problem solved! Cpu fan does not spin until cpu sensor warms up and tells fan to spin. I was worried cpu would be damaged because fan did not spin after booting pc. I was unplugging the power after 6 seconds into power up, as I thought the fan would not spin at all. After talking with Gigabyte tech, I plugged the cpu fan into the cpu power header on mobo and waited an agonizing 8 seconds as I booted the computer and sure enough the fan is spinning correctly. For sure a new learning curve for me. I now understand this mobo is designed like this.