Why the Intel B460 and H470 lack Rocket Lake-S support

Next month we'll see the launch of Intel's Rocket Lake-S processors. Unfortunately, not all existing LGA1200 motherboards will support the new chip. As was covered earlier this week, only the Z490 and H470 are getting Rocket Lake-S support.

Is this shenanigans or is there a good technical reason why chipsets like the H410 and B460 lack an upgrade path? TechPowerUp came across an explanation. Some batches of the B460 and H410 are rebadged from older generations of PCH, and are fabbed on 22nm. The chip giant likely did this to free up capacity on its 14nm node to produce more processors, which have higher margins. The result is that these 22nm B460 and H410 chipsets lack features that are required for Rocket Lake-S:

In addition to being limited to an older version of Intel ME (Management Engine), the H460 and H410 PCH lack the ability to communicate with "Rocket Lake-S" processors over side-band, using PMSYNC/PMDN signals, a design change Intel introduced with the "Tiger Lake" and "Rocket Lake" microarchitectures. The chipsets faced no such limitation with "Comet Lake-S." Intel's decision to re-badge older 22 nm-class PCH silicon as B460 and H410 may have been dictated by the company's 14 nm node volume constraints. HotHardware reports that some motherboard vendors, such as GIGABYTE, found a clever (albeit expensive) way around this limitation, by creating "V2" revisions of their existing B460 and H410 motherboards, which actually use the 14 nm H470 chipset.

There are also some rumors that not all Z490 motherboards will be able to support Rocket Lake-S due to changes in the requirements for the power delivery system. More news about this will likely follow in the coming weeks.

Source: Hardware Zone