Intel Xeon Phi 7250 socket: LGA 3647
The Intel Xeon Phi 7250 uses the LGA 3647 socket on KNL server boards. It is a 68 core Knights Landing part at 1.4 GHz and 215 W with MCDRAM for efficient dense nodes.
- Socket
- LGA 3647
- Launched
- June 20, 2016
- Cores and threads
- 68 and 272
- Base power
- 215 W
- Codename
- Knights Landing
- Segment
- Server
- Family
- Intel Xeon Phi
- Clocks
- 1.4 / 1.6 GHz
Intel Xeon Phi 7250 specifications
| Cores | 68 |
|---|---|
| Threads | 272 (4 per core) |
| Core architecture | Knights Landing cores on 14 nm |
| Clocks | 1.4 GHz base, up to 1.6 GHz |
| Cache | 34 MB L2 (512 KB per core, no L3) |
| Processor base power (TDP) | 215 W |
| Manufacturing process | 14 nm |
| Memory support | DDR4-2400, six channels, up to 384 GB, plus 16 GB MCDRAM |
| PCI Express | PCIe 3.0, up to 36 lanes |
| Integrated graphics | None (server CPU) |
| Multiplier | Locked |
| ECC memory | Supported (DDR4) |
| Package | LGA 3647 (3647 contacts) |
| Launch price | Intel recommended customer price |
Motherboard compatibility
Intel Xeon Phi 7250 needs a motherboard with a LGA 3647 socket. Chipset by chipset data for this codename is not recorded yet. See the LGA 3647 chipset list and the board maker's CPU support list.
LGA 3647 at a glance
| Type | LGA, 3,647 contacts |
|---|---|
| Package size | 76.0 × 56.5 mm |
| Introduced | 2016 |
| Memory | DDR4-2933 ECC, six channels, up to 2 TB |
| Cooler mounting holes | Board specific (narrow and square ILM heatsinks) |
What the Xeon Phi 7250 is
The Xeon Phi 7250 brings Knights Landing to LGA 3647 for efficient dense nodes with stacked memory. It launched on June 20, 2016 with 68 cores at 1.4 GHz base and up to 1.6 GHz boost at 215 W. Intel targets clusters that need more cores per watt with high bandwidth memory.
Thirty four megabytes of L2 with 512 KB per core carry tiles without L3. Four threads per core give 272 threads. The mesh joins tiles, memory and I/O on die.
Sixteen gigabytes of on package MCDRAM deliver over 400 GB/s beside DDR4-2400 pools up to 384 GB. The process is 14 nm. The multiplier is locked. AVX-512 units speed vector loops.
Buyers choose the board at order time with memory and cooling tier. The 215 W rating needs 2U airflow. MCDRAM flat mode suits large arrays that planners tile by hand.
Socket and motherboard compatibility
The Xeon Phi 7250 fits LGA 3647 on KNL server boards with DDR4 slots. Makers list Knights Landing with 2016 BIOS builds. Early stock may need an update.
Bootable host builds run Linux directly on the chip. The 7250 balances core count with 215 W for perf per watt racks. The Socket vs chipset: what decides whether a CPU works guide covers matching.
Single socket HPC nodes are the deployment. Growth means more LGA 3647 nodes. Power needs metered racks.
Memory, PCIe and cooling
DDR4-2400 in six channels up to 384 GB suits dense jobs. Sixteen gigabytes of MCDRAM lift bandwidth bound loops. Test flat mode first for large arrays.
PCIe 3.0 with up to 36 lanes from the CPU serves HBAs and NICs. Boards split lanes between risers and NVMe. Fabric options cut add in cards.
Cooling follows server practice with vendor heatsinks for 215 W classes. No cooler ships in the box. ECC guards DDR4 memory.
Upgrade paths
On the same socket, the Intel Xeon Phi 7230 gives 64 cores tuned for bandwidth per core. The Intel Xeon Phi 7250F shares 68 cores at 230 W for fabric builds. Both share LGA 3647 boards.
The Intel Xeon Phi 7290 moves to 72 cores for top nodes. It needs the same boards.
Past HPC nodes move to Xeon Scalable. The Phi 7250 covers 2016 clusters where efficient dense cores with stacked memory must deploy.
Frequently asked questions
What socket does the Intel Xeon Phi 7250 use?
It uses LGA 3647 on KNL server boards.
How many cores does the Xeon Phi 7250 have?
Sixty eight cores with four threads each give 272 threads. Base is 1.4 GHz with boost to 1.6 GHz.
Which graphics does the Xeon Phi 7250 include?
None. Serial and network manage the node.
What memory does the Xeon Phi 7250 support?
DDR4-2400 up to 384 GB plus 16 GB of on package MCDRAM.
When did the Xeon Phi 7250 launch?
June 20, 2016 with Knights Landing parts.
Sources and verification
Facts last checked against these sources on . Page last edited on .