AMD EPYC 4345P socket: AM5

What the AMD EPYC 4345P is

The AMD EPYC 4345P is the 8-core member of the EPYC 4005 Grado stack on Socket AM5. It runs 16 threads at 3.8 GHz base with boost to 5.5 GHz, backed by 32 MB of L3 cache and a 65 W default TDP. AMD launched the EPYC 4005 series on May 13, 2025 at a 1Ku price of 329 USD, building Grado on the same Zen 5 chiplets as Granite Ridge desktops with a 4 nm compute die and a 6 nm I/O die.

Eight Zen 5 cores at these clocks suit small business servers, hosted VPS nodes, branch file servers and test labs that need server management and ECC without a large socket. High base clocks keep single-threaded business apps responsive, while 16 threads cover file, mail and light virtualization side by side. The 65 W envelope fits tower and short-depth rack chassis with standard air cooling.

Against the 6-core AMD EPYC 4245P below it, the 4345P adds 2 cores for busier multi-tenant hosts. Against the 12-core AMD EPYC 4465P above it, the 4345P keeps higher base clocks for license-per-core sites at the same 65 W class. The AM5 socket keeps board costs near desktop levels while adding ECC and RAIDXpert2 for servers. See Socket vs chipset: what decides whether a CPU works for how socket, platform and firmware fit together on AM5 server boards.

Socket and motherboard compatibility

The 4345P fits Socket AM5, a 1,718-contact land grid array shared with Ryzen 7000 Raphael and Ryzen 9000 Granite Ridge desktops such as the AMD Ryzen 9 9950X. Every Grado board is single-socket only, so one 4345P fills the socket and there is no second-socket upgrade to plan. Server AM5 boards add ECC validation, BMC management and RAIDXpert2 on top of the desktop socket, so board choice follows the server vendor CPU list.

Grado uses the same AM5 socket as the EPYC 4004 Raphael range, so many AM5 server boards take the 4345P after a BIOS update from the board maker. A 4345P at 65 W fits boards already rated for 65 W Grado and Raphael parts, which keeps thermals simple. Memory must be ECC-capable DDR5 where the workload needs it, and the vendor memory list governs exact speeds. Moving from any other socket is a full platform change with board, memory and heatsinks replaced together.

Memory, PCIe and cooling

Each AM5 socket feeds 2 DDR5 channels with ECC UDIMM or RDIMM support, and AMD rates Grado to 5600 MT/s for up to 192 GB per socket. Two channels at these rates keep 16 threads supplied in file, web and light virtualization mixes. Population order and maximum capacity vary by board, so the vendor memory list governs every build, and ECC should stay enabled for business data.

PCI Express connectivity is Gen 5 with x28 lanes from the CPU, rising to x44 with the board chipset for slower slots and devices. That lane budget feeds NVMe boot and data drives plus 10 and 25-gigabit networking on an entry server without strain. Lane splits between graphics, NVMe and expansion slots follow the board block diagram, so architects confirm slot maps before adding cards.

Cooling uses standard AM5 retention at 54 × 90 mm with the fixed AM5 backplate, and the 4345P at 65 W suits tower air coolers and 1U server heatsinks rated for that class. No cooler ships with the boxed server part in most channels. Firmware power limits can cap draw below the default where a quiet office tower demands it, at some cost in sustained clocks.

Upgrade paths

On the same socket, the path up from the 4345P starts with the 12-core AMD EPYC 4465P and the 16-core AMD EPYC 4545P, all staying on AM5 server boards at 65 W. The 170 W 16-core AMD EPYC 4565P follows for compute-heavy nodes where cooling allows. Each move keeps board and memory investments where the power class allows, plus a BIOS that already supports Grado.

The step down to the 6-core AMD EPYC 4245P trims core count for single-service boxes. A move to SP5 Turin is a different platform with 12 memory channels and 128 PCIe lanes, aimed at dense racks rather than entry towers. That change replaces board, memory population and cooling design from scratch. The decision turns on whether the site needs entry tower economics or rack density.