Determining Correct Microcode for i7-3930k

I’ve managed to confuse myself a bit regarding the correct microcode for my processor (and if I should I upgrade it).

I’m using an i7-3930k, CPUID 206D7 (I think, conflicting reports - some say 206D5). I see that Intel has released a new microcode, version 713, for this CPUID as of 1/26/2018.

However, two things seem a bit off:
1. UBU lists the microcode in my current BIOS, version 710, as being outdated and version 713 does appear in UBU’s available microcode database - but the automatic upgrade option only offers 710. In order to get it to list 713 I need to manually select the microcode file I’d downloaded/extracted from the Intel site.
2. The list provided by Intel at https://newsroom.intel.com/wp-content/up…te-guidance.pdf does list my CPUID as being production ready, but not the specific CPU name. (The i7-3930k is a Xeon with 2 cores disabled, Intels sheet lists the Xeon models but none of the i7 models using the same CPUID.)

http://www.cpu-world.com/CPUs/Core_i7/In…20i7-3930K.html - lists it as 206D5 at the top of the page and 206D7 at the bottom.
EDIT: http://www.cpu-world.com/sspec/SR/SR0H9.html#cpuid - and here it is listed as 206D6


So, should I be safe to go ahead with the microcode update - or should I hold off?

So, i 've the same processor like you and no issue during upgrade microcode to 713, CPUID 206D7, using latest UBU and MMtool 5.0.0.7.
Now am patched against spectre, with a slower performance result, but honesty i don’t see any difference about performance, maybe a benchmark test show that.
Good luck.

Walls.

deadspectre.PNG

meltspectdead.PNG

@Walls
Excellent, thank you. One more question then, I see your bios file retained the microcode for several other CPU’s, when I update mine I go from what I have here in “original.jpg” to what I have in “modified.jpg”. How did you get yours to update just the one line and not replace everything with redundant entries?

Or did you use the dev version of UBU?

original.jpg

modified.jpg

Yes using the dev build of UBU, create ffs and upgrade, the latest stable UBU show me latest microcode too.

micro.PNG



Walls.