The other microcodes I believe are for other generation + server based processors which for most of us not needed. Even though my FIT table detailed four modules you really need to update just the one for your particular cpu. Go to the CPU Microcode repository and locate the cpu microcode modules that are appropriate for your platform. Step 2 - Extract Body of master microcode module and save: Just ‘Replace Body’ in UefiTool will be sufficient. In the case of individual microcode rom modules its a lot easier to manage in that probably you won’t need to copy paste the microcode hex values in a hex editor.

Sometimes you may find each microcode in their own individual rom module: In my case my master microcode file resides in the rom module with GUID ‘17088572-377F-44EF-8F4E-B09FFF46A070’. Select the first microcode entry in the FIT table by doubling clicking item #2 as illustrated above and you will note that UEFITool A40 will automatically finds the actual master microcode file for us to manipulate.

Then you have a number of references to the location of the actual microcode entries followed by possibly Bios initialization and ACM modules, Bootgaurd modules, and TPM/TXT modules of which may or may not be present depending on the bios. Take note that there will be a number of entries with the first one being a reference to ‘FIT’ table. Load your bios file in UEFITool A57 and select the ‘FIT’ tab on the lower panel.

UEFITool A67 download the new version