Hello The BMC controls fan speeds. If the BMC is not initializing then they will run at 100%. You will likely experience performance issues as well because throttling of the CPU and memory will also occur if the BMC is not functioning correctly. You can sometimes reflash the system BIOS and BMC, but the BMC has to be partially functional to be able to complete a firmware update. If the BMC is not initializing enough to be able to update firmware then you can try draining flea power from the system and completing no POST troubleshooting. Any hardware attached to the system can disrupt initialization of any other hardware, so no POST troubleshooting involves removing unnecessary hardware. If you recently made a change when this issue started then I would start with undoing that change. If updating, draining flea power, and removing unnecessary hardware has no effect then you will likely need to replace the system board to correct the issue. Thanks
The server gives a Baseboard management controller error at start up but starts and runs fine. The fans are running at 100% all the time. I have tried to update the BMC firmware but it gives and error This update package is not compatible with your system configuration. Also the status light on the back is lit up solid all the time.  Thanks for your help  
PowerEdge 2950 BCM controller error at start up