The blueprints of Intel’s 6th Gen Xeon Granite Rapids processors have surfaced. Although this data is outdated, it shouldn’t differ much from the final numbers. Like Cascade Lake, it’ll feature two separate platforms, Granite Rapids-SP/Birch Stream-SP and Granite Rapids-AP/Birch Stream-AP. The former will top out at 80, with the latter packing up to 120 cores.
Contrary to the latest rumors, these documents claim that Granite Rapids will leverage the Redwood Cove core architecture. A whole generational core architecture upgrade is unlikely, so I expect a revision of the same Redwood Cove design. Granite Rapids-SP will leverage LGA 4677 with a TDP of up to 350W, while Granite Rapids-AP will adopt the much larger LGA 7529 socket with a power ceiling of 500W.
Granite Rapids-SP on Birch Stream-SP will feature a quad-chiplet design with two P-core dies fabbed on the Intel 3 process, and two I/O dies manufactured using the Intel 7 node. This is where the specifications have been upgraded from Intel 7 to Intel 3. Conversely, these could be the older node naming scheme, in which case we are looking at the same node (Intel 4->Intel 3 is largely a refresh with HP EUV libraries).
Granite Rapids-AP on Birch Stream-AP will consist of three Redwood Cove compute tiles, topping out at 40 cores each or 120 overall. It’ll feature 12-channel DDR5 memory and 96 PCIe Gen 5 lanes alongside 6 UPI2. Granite Rapids-SP will have 8-channel DDR5 memory, 88 PCIe Gen 5 lanes, and 4 UPI2 lanes for CPU-to-CPU interconnections.
Sierra Forest will be socket compatible with Granite Rpaids. We’re looking at an “E” core count of 384 or 512. The blueprint doesn’t include a tiled design for Sierra Forest, but I highly doubt that Intel will design a 384-core monolithic chip. Multiple 128-core tiles are more likely.