Intel Xeon Platinum 8480+ socket: LGA 4677

What the Xeon Platinum 8480+ is

Intel positions the Xeon Platinum 8480+ as the 56-core member of the 4th Gen Xeon family for LGA 4677 boards from January 2023. 56 cores with hyperthreading give 56 cores and 112 threads, with base at 2.0 GHz and up to 3.8 GHz turbo. The package carries 105 MB of Smart Cache. The 350 W envelope needs a high capacity server heatsink with front to back airflow and a chassis rated for continuous full load.

DDR5 to 4800 MT/s with one DIMM per channel and 4400 MT/s with two DIMMs per channel in 8 channels with ECC feeds the cores, and matched DIMMs hold the rated speed. Eighty Gen5 lanes with Flex Bus and CXL per CPU wire NICs, accelerators and NVMe, and the lane count stays constant across most Sapphire Rapids server SKUs. Four UPI links at 16 GT/s join sockets into a coherent fabric, while board firmware sets the exact topology.

Flagship scale out and cloud hosts take this 56-core Platinum with more than 100 MB of shared cache, where dual socket pairs carry the largest VM counts. Boards need a C741 class chipset with the Xeon Platinum 8480+ on the CPU support list, not W790 workstation boards. The Socket vs chipset: what decides whether a CPU works guide covers board choice, and Intel Xeon Platinum 8461V shows a nearby option on the same socket.

Socket and motherboard compatibility

The 8480+ fits LGA 4677 on single and dual socket server boards with LGA 4677 retention and server power delivery. Board lists must name the Xeon Platinum 8480+ part for qualification. W790 workstation boards target W-series chips instead, so a server SKU will not post there even though the contact count matches.

Server chipset choice decides management and IO breadth rather than CPU fit. C741 class boards carry BMC management, multiple NICs and NVMe backplanes for this power class. A BIOS that lists Sapphire Rapids from January 2023 covers the part, while early firmware may need an update for specific stepping IDs. Check the board CPU list before mixing this SKU with other steppings.

Memory, PCIe and cooling

DDR5 to 4800 MT/s with one DIMM per channel and 4400 MT/s with two DIMMs per channel in 8 channels with ECC feeds the cores, and matched DIMMs hold the rated speed. Population with matched DIMMs holds the rated speed, and eight channel operation needs one DIMM per channel at minimum for full bandwidth. Capacity reaches 4 TB per socket with high density DIMMs.

Eighty Gen5 lanes with Flex Bus and CXL per CPU wire NICs, accelerators and NVMe, and the lane count stays constant across most Sapphire Rapids server SKUs. Lane bifurcation follows board firmware, so slot population rules come from the board manual.

The 350 W envelope needs a high capacity server heatsink with front to back airflow and a chassis rated for continuous full load. The 77.5 × 56.5 mm FCLGA4677 package uses a server carrier with even mounting pressure. Paste and torque sequence follow the heatsink maker specification for 350 W parts.

Upgrade paths

On LGA 4677 the upward moves are higher core Platinum parts where VM counts grow, or adding a second Xeon Platinum 8480+ socket where boards allow two socket operation. For this 56-core SKU, memory growth to full channel population and NIC additions often help more than clocks.

Outside this SKU, Intel Xeon Platinum 8461V (Xeon Platinum 8461V) on LGA 4677 trims or adds cores for lighter or denser loads. Platinum parts add UPI breadth for larger fabrics, while Silver parts cut cost for single purpose hosts. A move to another socket needs a new board and memory plan, so socket local growth comes first.