Martin, The DRAC III is not a supported option on the R710. The only one that will function in the R710 is the iDRAC6, Express and Enterprise versions.  There aren't any instructions to be found for this process. Regards,  
PowerEdge R710 This currently has a Integrated Dell Remote Access Controller 6 - Express . Version 1.70 which we need to change to a DRAC III are there instructions, issues, or is it just a matter of power-down take the Express out, put the DRAC III in and the system will prompt - if anything - on power-up? Kind regards Martin
Changing DRAC 6 Express to DRAC III on an R710