Comment 4 for bug 1908840

For model 78 stepping 3 processors, look here:

https://github.com/intel/Intel-Linux-Processor-Microcode-Data-Files/issues/31

To put it bluntly: update your system firmware. If no such update is available, pressure the system vendor into releasing one. For now, that's the only available fix. The alternative is to not attempt to update the processor microcode at all -- and remain vulnerable to the security and reliability issues the microcode update would have fixed.