Intel Alder Lake-S CPUs To Feature DDR5 Memory Support on LGA 1700 Motherboards, Rocket Lake-S Desktop CPU TDPs Detailed

Intel's Alder Lake-S & Rocket Lake-S Desktop CPUs will mark the first major departure from the 14nm process node and the Skylake core architecture, respectively. Intel is expected to ship the latest desktop families by late 2020 and late 2021/early 2022 but it looks like rumors have already started popping up on these chips from Chinese based PTT forums.

Just a few days ago, new details for Intel Alder Lake-S Desktop CPUs leaked out, confirming the use of the LGA 1700 socket. Now some interesting details have been revealed by SharkBay whose leak history is very solid. The details mention that Alder Lake-S CPUs will indeed be supported by a new LGA 1700 socket which will feature two tiers of motherboards.

But the main feature for the Alder Lake-S Desktop platform will be the support for next-gen DDR5 memory. The same leaker mentions that the two motherboard tiers are necessary as they'd have different DDR5 support. Alder Lake-S CPUs will support DDR5-4800 MHz memory natively but only the higher-tier 6-layer motherboards will be able to support 2 DIMMs per channel whereas 4-layer motherboards would feature support for a 1 DIMM per channel. It looks like Alder Lake-S will retain a dual-channel memory design but only higher-end motherboards would get support for the faster memory.

The 4-layer motherboards featuring the LGA 1700 socket and 1DPC will support up to 4000 MHz speeds natively. This is still a large jump from the current DDR4-2933 native support. But for those who'd be planning to equip faster memory would also have to get the more expensive 6-layer LGA 1700 motherboards. It is also stated that the Alder Lake-S circuit design is completed but the exact production date for the chips is not yet confirmed.

As for Rocket Lake-S CPUs, SharkBay has also mentioned the TDPs for the successor of Intel's 10th Gen Comet Lake-S CPUs. The Intel Rocket Lake-S CPUs will retain support on Z490 motherboards & the LGA 1200 socket but as we've learned through various leaks, will be replacing the older Skylake architecture with a brand new chip architecture that is either base on the Sunny Cove or the Willow Cove design. Sharkbay has mentioned TDPs and PL limits for various 8, 6, and 4 core SKUs that will be featured in the lineup. Following is a table from Videocardz which shows the exact TDP and PL1 / PL2 distribution we can expect on the 11th Generation Desktop family:

Previous details for Alder Lake-S CPUs have revealed that the next-generation desktop family is to launch sometime in late 2021 or early 2022. The Alder Lake CPUs could be the first 10nm desktop parts from Intel, featuring a hybrid architecture design.

Intel's Alder Lake-S would be a totally different beast than anything we've seen from Intel yet, utilizing the 10nm++ process node which is an evolution of the 10nm+ process node (the same node used to fabricate Tiger Lake CPUs). The Alder Lake-S 12th Generation Core lineup would feature a new design methodology, supporting a mix of big and little cores as we had reported earlier. Three configurations of the Alder Lake-S CPUs were leaked which included:

As you can see, the CPUs will feature various configurations with a max of 8 high-performance and 8 efficiency-optimized cores. There's the unlocked variants with 125W and locked variants with 80W TDPs. There's also a 6 (big) core configuration which doesn't include efficiency optimized cores but it looks like Intel plans to offer the higher end variants without the smaller cores too. While the chip design methodology isn't anything new as we have seen several mobility SOCs feature similar core hierarchy, it would definitely be interesting to see a similar outing on a high-performance desktop CPU lineup.

With that said, the Alder Lake-S CPUs will feature support on a newer LGA 1700 socket and will feature an enhanced variant of the Xe GPU which will be available by the time of its launch. Intel is also investigating performance scaling of Alder Lake-S CPUs with TDPs as high as 150W that would be a true enthusiast desktop part, something to challenge the likes of the Ryzen 9 3950X 16 core processor in the desktop department.

The same Chiphell rumor that is mentioned above also states that the Alder Lake-S CPUs will be utilizing Intel's Golden Cove architecture to power the big cores and Gracemont, the generation after Tremont to power the Small cores. Following are some of the updates you should expect from Intel's 2021 architecture lineup:

Intel Golden Cove (Core) Architecture:

Intel Gracemont (Atom) Architecture:

Golden Cove would be a big architectural jump over Willow Cove, offering an entirely new design and a range of improvements to power the bigger cores while Gracemont would do the same for Tremont, offering higher performance per watt in smaller but efficient cores.

Intel's Rocket Lake-S desktop CPU platform is expected to feature support on LGA 1200 socket which will make its debut with Comet Lake-S CPUs although on 400-series motherboards. The Intel Rocket Lake-S processors will be launching alongside the 500-series motherboards so it marks one major question as to whether the CPUs will be kept backward-compatible with 400-series chipset based LGA 1200 socket or will they only come land in exclusive support on 500-series boards. In the case of the latter, the Comet Lake-S and 400-series platform would be very short-lived since the Rocket Lake lineup is expected later this year and Comet Lake-S CPUs will be available around May-June 2020. This would be a much faster replacement than what we saw when going from Kaby Lake to Coffee Lake back in 2017.

The Coffee Lake lineup, although being supported by the same LGA 1151 socket, was supported exclusively by the Z370 motherboards. Intel suggested that due to a new pin layout on the Coffee Lake processors, the updated motherboards were required although many enthusiasts bypassed this restriction and booted their Coffee Lake CPUs on Z270 motherboards. We may see a similar thing happening with Rocket Lake and LGA 1200 considering the updated microarchitecture and design of the new chips.

Other features of Intel's Rocket Lake Desktop CPUs include:

Once again, the reason I think that Rocket Lake is using Willow Cove cores is that Tiger Lake with the same architecture features Xe Gen 12 graphics while Ice Lake with Sunny Cove cores is using the Gen 11 GPU. It is possible that the cache is different on desktop chips but once again, that remains to be confirmed and until we see more leaks, this is up for debate.

Overall, the Rocket Lake-S family is expected to launch later this year with Alder Lake-S targetting a late 2021 or early 2022 launch timeframe. That would be around the same time when AMD is expected to launch its own DDR5 platform based around the rumored AM5 socket with support for Zen 4 based Ryzen 5000 CPUs which will definitely be something to look forward to.