  When the server is restarted the iDRAC/BMC loses communication with the system BIOS until it completes POST. During that time it will run all of the fans at maximum. It sounds like the iDRAC/BMC is not re-establishing that connection to the system BIOS correctly until it is restarted. If there is any USB device attached to the server then disconnect it and test again. If the issue still persists then remove any add-on cards and test again. If the issue still persists then the iDRAC express and possibly the system board should be replaced. The most likely cause of the problem in my opinion is cache on the iDRAC express. If you have the same model server available to swap parts from then you can swap the iDRAC express to test. Thanks
Hi everybody, please help... I don't know what to do anymore. Since I bought some R610 units I've been trying to make the server less noiser and 2 weeks ago I've though that I nailed it.. but no. I have managed to update the server idrac firmware to version 1.96, right after I updated the firmware the fans stepped down from 8000 RPM to 4500 RPM, and that was exactly what I needed. Today I needed to reboot the machine and guess what.. when I rebooted the server the fans went back to 8000 RPM. Please someone knows what happened? I have no idea, google isn't my friend this time. 
R610 fan noise back after reboot