Intel Xeon Platinum 8558 5th Gen Server Processor, 48-Core, LGA4677
The Intel Xeon Platinum 8558 is a server processor with forty eight cores and ninety six threads, built on Intel's 5th generation Xeon Scalable architecture, codenamed Emerald Rapids. It runs at a base frequency of 2.10 GHz and reaches 4.00 GHz under Turbo Boost, backed by 260 MB of cache within a 330 W thermal envelope. It installs in an FCLGA4677 socket, scales to two sockets, and supports up to 4 TB of eight channel DDR5 at 5200 MT/s, which places it in the current generation of dual socket rack servers.
About Intel →Specifications
Additional details
Compatibility and integration considerations
This processor uses the FCLGA4677 socket shared with 4th generation Xeon Scalable, so an Emerald Rapids part can go into a Sapphire Rapids board once the BIOS supports it, which is worth confirming against the board vendor rather than assuming. Memory runs in eight channels of DDR5 at 5200 MT/s with a 4 TB ceiling and ECC throughout, and the quoted speed applies at one DIMM per channel. The part scales to two sockets. PCI Express is revision 5.0 with 80 lanes, which is what makes it viable for accelerator and NVMe dense builds. The 330 W envelope is the constraint on integration: chassis airflow, heatsink rating and power delivery all have to be specified for it, and it is more than three times the envelope of the Silver 4214R in the same family.
Typical use cases
This processor is specified into new dual socket rack servers for virtualisation, database and AI inference workloads, where the built in Intel AMX instructions do the heavy lifting on inference without a discrete accelerator. It is the one processor in this catalog still in full production rather than being sourced for replacement, so it is the part to quote for a new build rather than a fleet repair.
