I would recommend following the recommendations listed in our article System Fan Runs Too Fast or Too Loud. I noticed you mentioned you already updated the BIOS. Do you recall which selection you chose for the FRUSDR?
Additionally, the chassis you are using uses 3 system fans, aside from the processor fans. Make sure the fans are connected on SysFan1, SysFan3, and SysFan5.
If the issue remains, please run our Intel System Information Retrieval Utility to review the information of your logs.
Thanks so much David!