Server Processors - Intel Xeon & AMD EPYC

Which processors each PowerEdge generation takes

Every PowerEdge generation is built for specific processor generations and one memory type, so the server model tells you which CPU to order. Dell's documentation lists:

Intel's specifications show why the generations do not cross over: ARK places the first two Xeon Scalable generations on socket FCLGA3647, the third on FCLGA4189 and the fourth and fifth on FCLGA4677, and it gives the E5-2600 v2 family DDR3 memory against DDR4 for v3 and v4. Shop every Xeon family on Intel Xeon processors and the servers on Dell PowerEdge servers.

Server CPUs vs desktop CPUs

A server CPU is built around memory and I/O, and the makers' own specification pages show it when a desktop flagship is set beside a server part of the same era:

Intel lists that Core i9 as single-socket only, while its Gold counterpart runs in two-socket servers and EPYC 9004 parts in one- or two-socket servers. The extra channels and lanes are what let a server hold terabytes of memory and a full set of NICs, HBAs and NVMe drives.

One socket or two

A second processor brings its own memory channels and PCIe lanes, not only more cores. Dell's R740 technical guide states that the server runs normally with one processor in the CPU1 socket, with the CPU2 blanks installed, but that only Riser 1 and Riser 2B work in that configuration, and Dell's R740 manual populates memory sockets B1 to B12 only when the second processor is present. AMD builds some EPYC models for single-socket servers only and marks them with a P suffix.

Xeon Scalable tiers, E5 and E7

Xeon Scalable comes in four tiers, Platinum, Gold, Silver and Bronze, and the three larger tiers have pages of their own: Xeon Gold, Xeon Platinum and Xeon Silver. Xeon E5-2600 v2, v3 and v4 processors are grouped under Xeon E5, the Xeon E7 family under Xeon E7, and AMD's server chips under AMD EPYC processors.

Before you order

1. Look up your server's generation in the table above.
2. If you add a second processor, give it the same memory configuration as the first: Dell's R740 manual requires identical memory on each processor in a dual-processor server.
3. Match the memory generation to the processor: browse server memory.

Server CPU questions

Can I use a desktop CPU in a server?

Not in a server built for Xeon Scalable or EPYC. The sockets differ: Intel puts its 14th-generation desktop Core i9 on FCLGA1700 and 4th Gen Xeon Scalable on FCLGA4677, and AMD puts Ryzen 9 7000 desktop chips on AM5 and EPYC 9004 on SP5. AMD also lists unbuffered DIMMs for that desktop chip, while two-socket servers run registered memory. Order from the processor family your server's documentation lists.

Do I need two processors in my server?

Only if you need what the second socket brings. Each processor adds its own memory channels and PCIe lanes: on Dell's PowerEdge R740, memory sockets B1 to B12 work only with the second processor installed, and with one processor only Riser 1 and Riser 2B are functional. If one processor's cores, memory channels and slots cover the workload, a single-socket build is supported.