The microcode in this bios is 52kb but attempting to replace it with anything bigger fails when it rebuils (ie. changes wont stick)
However , a lot of the 52kb microcode is just blank - its been padded out to reach 52kb in size but theres not 52kb worth of microcode in it!
I looked up E8400 E0 and it has a CPUID of 1067A. I have 3 microcodes in my collection for this CPU and , after some careful cutting and pasting , reintegrated them into the existing microcode without changing the filesize. I then rebuilt the bios and because the file had not changed size , the changes stuck!
So now in theory the microcode for E8400 (E0) is in your bios.
Flash at your own risk!
Ready to go floppy disk image (IMPORTANT THAT YOU FLASH FROM A FLOPPY DISK , Other methods have had reported problems with Lenovo models like flashes not writing properly)
I made bootable USB flash disk and try to flash my BIOS with your latest file, using DOS. I renamed it like my original BIOS file $image54.usf. And got this error:
Later I noticed that your latest BIOS mod file has bigger file size:
Is that all OK about bigger file size? Also I have opened my original BIOS file and your latest file with Hex Workshop and saw that they have different file beginings. Is that OK too?