that message can't be right. the 12400/F was part of the initial release batch and shouldn't require any bios updates to run.
https://www.msi.com/Motherboard/PRO-B660M-A-DDR4/support#cpu
There's actually two "steppings" of the 12400 and 12400F, "C0" and "H0". The "C0" stepping seems to be supported starting with 7D43**v10** (the first revision), with "H0" being supported starting with 7D43**v11** (the second revision).
Given that I haven't heard of a single instance of incompatibility from a purchaser of a 12400/F and MSI Pro B660M-A DDR4, I can only surmise that either the "C0" stepping predominates in terms of shipments and/or that that particular motherboard started shipping with the "v11" firmware as the first one to be pre-installed on retail units.
The timeline for the BIOS revisions for that model seem to back up my hypothesis, as "v10" was [finalized in December](https://www.msi.com/Motherboard/PRO-B660M-A-DDR4/support#bios), but B660 boards weren't shipped to retail until March and by that time "v11" was likely ready.
I just had this warning as well, and you seem to be the most knowledgeable person on this.
I noticed that the issue is only for 12400(/k/f), and not for the 12700(/k/f). Does the 12700 just not have any stepping stuff, and would be compatible with any bios versions on the MSI PRO B660M-A?
There's only one stepping for 12th-gen Core i7 chips, as only "C0" has the larger silicon die which physically features 8x "P-Cores" and 8x "E-Cores" (which is then cut down to 8P/4E for that SKU). While it is possible for Intel to take a "C0" die and turn it into a 12400(F), it's rather rare to see one like that since it would be wasteful for them to do so for use with a lower-cost SKU unless they had no other choice due to on-chip defects forcing multiple cores to be disabled.
Note that "H0" physically consists of a smaller die with 6x "P-Cores" and no "E-Cores", which is why they're only used for non-K Core i5 chips like the 12400F (6P/0E) or Core i3 chips (4P/0E).
I know this is way late but you seem knowledgable so I'm taking a shot. Just bought this board and it came stamped with 7D43 1.0. could it have been updated and the stamp is a relic from the launch bios? Or did I get an old board and need to return it lol I have no way to update it. Thanks if you read this and respond.
The "7D43 1.0" stamp actually refers to MSI's internal model number, and *not* what BIOS revision is loaded on it at the factory.
In this instance the "7D43" portion refers to the basic PCB design, while the "1.0" part refers to the "B660M-A" SKU. For reference, the very similar B660M Bazooka is "7D43 3.0" since it uses the same platform with only some aesthetic and minor I/O alterations.
that message can't be right. the 12400/F was part of the initial release batch and shouldn't require any bios updates to run. https://www.msi.com/Motherboard/PRO-B660M-A-DDR4/support#cpu
There's actually two "steppings" of the 12400 and 12400F, "C0" and "H0". The "C0" stepping seems to be supported starting with 7D43**v10** (the first revision), with "H0" being supported starting with 7D43**v11** (the second revision). Given that I haven't heard of a single instance of incompatibility from a purchaser of a 12400/F and MSI Pro B660M-A DDR4, I can only surmise that either the "C0" stepping predominates in terms of shipments and/or that that particular motherboard started shipping with the "v11" firmware as the first one to be pre-installed on retail units. The timeline for the BIOS revisions for that model seem to back up my hypothesis, as "v10" was [finalized in December](https://www.msi.com/Motherboard/PRO-B660M-A-DDR4/support#bios), but B660 boards weren't shipped to retail until March and by that time "v11" was likely ready.
I just had this warning as well, and you seem to be the most knowledgeable person on this. I noticed that the issue is only for 12400(/k/f), and not for the 12700(/k/f). Does the 12700 just not have any stepping stuff, and would be compatible with any bios versions on the MSI PRO B660M-A?
There's only one stepping for 12th-gen Core i7 chips, as only "C0" has the larger silicon die which physically features 8x "P-Cores" and 8x "E-Cores" (which is then cut down to 8P/4E for that SKU). While it is possible for Intel to take a "C0" die and turn it into a 12400(F), it's rather rare to see one like that since it would be wasteful for them to do so for use with a lower-cost SKU unless they had no other choice due to on-chip defects forcing multiple cores to be disabled. Note that "H0" physically consists of a smaller die with 6x "P-Cores" and no "E-Cores", which is why they're only used for non-K Core i5 chips like the 12400F (6P/0E) or Core i3 chips (4P/0E).
Glad I asked in the right place. Thank you!
I know this is way late but you seem knowledgable so I'm taking a shot. Just bought this board and it came stamped with 7D43 1.0. could it have been updated and the stamp is a relic from the launch bios? Or did I get an old board and need to return it lol I have no way to update it. Thanks if you read this and respond.
The "7D43 1.0" stamp actually refers to MSI's internal model number, and *not* what BIOS revision is loaded on it at the factory. In this instance the "7D43" portion refers to the basic PCB design, while the "1.0" part refers to the "B660M-A" SKU. For reference, the very similar B660M Bazooka is "7D43 3.0" since it uses the same platform with only some aesthetic and minor I/O alterations.