Dell recommend using SMS and Dell OpenManage Client Instrumentation (OMCI). However, this requires WMI scripting which may be prevented if security lockdown settings prevent such scripts from running.
Pros: Exposes the Dell BIOS to WMI and therefore enables almost any modification to be made by running VB script. It also means SMS hardware inventory can then report upon BIOS settings by extending the SMS_DEF.MOF.
Cons: Requires agent software to be run on the client.
The Dell Client Configuration Utility (DCCU) can be used as an alternative to the OMCI client to create stand-alone executables that can output configuration settings ('Get Values') to an XML file and/or configure BIOS settings ('Set Values'), including enabling WOL.
Pros: Leaves not footprint on the client
Cons: An executable file needs to be created for every action you want to perform against the BIOS; meaning heavier network utilization.