UpdateXpress System Pack Installer can be used to acquire the latest UpdateXpress System Packs (UXSPs) or all the latest updates for a particular machine type and operating system. It can also be used to acquire the latest update for a particular type of update, if you know the update-id (filename) of an earlier update.
If you want to acquire the latest BIOS update for machine type 7979, and you already know the filename for an earlier version of the BIOS is ibm_fw_bios_gge134e_windows_i386, by specifying an update-id with the -L option, you can acquire the latest BIOS update for that system.
lnvgy_utl_uxspi_10.6_winsrvr_32-64 ac -i ibm_fw_bios_gge134e_windows_i386 -L
Or, if you want to see if a new update is available, but do not want to actually download the update, specify:
lnvgy_utl_uxspi_10.6_winsrvr_32-64 ac -i ibm_fw_bios_gge134e_windows_i386
-L --report