Although Intel never explicitly expressed it, the general expectation was the impending 11th Generation Rocket Lake processors would slot fine into the current LGA1200 motherboard with the 400-series chipset. If there was any doubt, multiple motherboard manufacturers have officially confirmed the processors' backward compatibility. Â
ASRock, for one, has already updated various product pages to affirm support for Rocket Lake. The new description now reads "Supports 10th Gen Intel® Core Processors and 11th Gen Intel Core Processors (LGA1200)," with the latter alluding to Intel's Rocket Lake-S chips. Thus far, the preliminary list of motherboards (via momomo_us) includes the various offerings from different tiers, such as the Z490 Aqua, Z490 Phantom Gaming-ITX/TB3, Z480 Creator, and H470 Steel Legend.
On the other hand, Biostar reportedly shared a banner advertising Rocket Lake-S support on the brand's Z490 motherboards. The vendor has also updated the motherboard product pages to reflect the change. However, it would appear that Rocket Lake-S's rapport might only be with the company's Z490 motherboards since the B460 product pages don't proclaim support for 11th Generation chips.
While it's possible to enable Rocket Lake-S processors on all LGA1200 motherboards, we suspect that support will vary from one motherboard vendor to another. Besides the shift to the Cypress Cove microarchitecture, one of Rocket Lake-S's biggest attraction is PCIe 4.0 support. Nonetheless, some vendors might not have initially purposed some of their 400-series offering to support PCIe 4.0, especially the entry-level motherboards. That could be the explanation of why Biostar didn't mention Rocket Lake-S support on non-Z490 motherboards.
The current consensus is that Intel will probably take advantage of CES 2021 to announce Rocket Lake-S, which should come accompanied by new 500-series motherboards. Availability, however, is another story. If one Twitter user's roadmap is genuine, Intel might not commence Rocket Lake-S mass production until January 2021, meaning that the processors won't be hit the retailer shelves until February or even March.