Often times you need upto BIOS level information of all machines in your enviornment, like below, to include detailed information of each machine at hardware level.

  Then use the attached Powershell script and execute it on a machine with ports accessibility to all servers and you get below inventory.

  By default the information contained in the AD does not give you server's BIOS information and mac address and for that you need to do additinal WMI calls. The script does all of that for you.