I have just updated to ZCM 10.2.2, and read the following in the release notes
5.2.3 Asset Inventory

This section contains information about issues that might occur with Asset Inventory. Unable to inventory the BIOS details for Windows 7 64-bit devices that have SMBIOS 2.0 or earlier installed

Workaround: None.

If you want to inventory the BIOS details for Windows* 7 64-bit devices, you must have SMBIOS 2.1 or later installed on these devices.
Our 64 bit Windows 7 machines, registered with ZCM do not show any info from the BIOS, so I am assuming this is the problem.

If that is the case, how do you install SMBIOS? Where do you download it?