Intel® Xeon™ 638

The Intel Xeon 638 is a workstation processor with 16 cores and 32 threads, built on the Granite Rapids architecture. It launched in Jan 2026. Clocks run from 3.2 GHz base to 4.8 GHz boost. A 72-MB L3 cache backs the cores (6.6 MB per core). It addresses DDR5 memory up to 2 GB across 4 channels. The chip drops into the FCLGA4710 socket and exposes PCIe 5.0 (80 lanes). Rated TDP is 180 W. Notable platform capabilities: AMX, AVX-512, Extended Page Tables (EPT), Control-flow Enforcement (CET).

The Intel Xeon 638 scores 3,835 in single-core performance and 55,877 in multi-core performance (PassMark CPU Mark ratings). From those two ratings Feex computes 14,639 for overall performance, 41,689 for productivity performance, 37,635 for creator performance, 64,259 for engineering performance and 25,474 for gaming performance. Its multi-core throughput works out to 3,492 per core, 1,746 per thread and 310 per watt. Its computed efficiency index is 1,091. Its performance index is 181, so its overall performance is 81% above the Intel Core i5-12400 (index 100). Each bar shows the score as a share of a reference ceiling, which is the larger of the 99th-percentile score across the Feex CPU database and a fixed baseline.

Scores for individual PassMark CPU Mark test categories. Higher is better. These are measured test scores, not computed from the single-core and multi-core ratings.

In the individual workload tests the Intel Xeon 638 scores 184,582 in integer math, 146,292 in floating-point math, 720,145 in compression, 35,870 in cryptography, 4,762 in physics simulation, 55,596 in vector SIMD, 372 in the prime sieve and 73,143 in sorting. Higher is better. Compared with the Intel Core i5-12400, it is 213% above in integer math, 219% above in floating-point math, 216% above in compression, 212% above in cryptography, 337% above in physics simulation, 258% above in vector SIMD, 455% above in the prime sieve and 223% above in sorting. Each bar shows the score as a share of that workload's reference ceiling, the larger of the 99th-percentile score across CPUs with a recorded value and a fixed baseline.

The Intel Xeon 638 has 16 physical cores and runs 32 logical threads. It does not use a hybrid performance and efficiency core layout. It runs 2 threads per core. It runs at a base clock of 3.20 GHz and boosts up to 4.80 GHz.

The Intel Xeon 638 is a workstation processor, belongs to the Intel Xeon family, uses the Granite Rapids architecture and carries the codename Granite Rapids. It launched in Jan 2026.

The Intel Xeon 638 has 1.75 MB of L1 cache, 32 MB of L2 cache and 72 MB of L3 cache. That adds up to about 105.8 MB of cache, or 6.61 MB per core. Each core has 2 MB of private L2 cache.

The Intel Xeon 638 has a 3-level cache hierarchy: L1 at 1.8 MB, L2 at 32 MB and L3 at 72 MB. L3 is the largest level and makes up about 68% of the cache listed here.

The Intel Xeon 638 supports DDR5 memory, addresses up to 2 GB of memory and uses 4 memory channels. It does not support DDR4 and LPDDR memory.

The Intel Xeon 638 uses the FCLGA4710 socket, supports PCI Express 5.0 and provides up to 80 PCIe lanes.

The Intel Xeon 638 has a rated TDP of 180 W.

Instruction sets, security, virtualization, AI acceleration and OS readiness. Features are listed as supported, explicitly not supported, or not recorded; a feature that is not recorded is not the same as unsupported.

The Intel Xeon 638 is manufactured by Intel. It launched at a price of $989.

The Intel Xeon 638 is also identified by the model number 638.

Feex has recorded 56% of the specifications it tracks for the Intel Xeon 638. Values Feex does not hold are shown as "Not recorded" rather than estimated.

Not recorded: Core Configuration: Efficiency Cores, All-Core Boost and Unlocked Multiplier. Architecture & Generation: ISA Family and Market Status. Cache: L4 Cache. Memory Support: Memory Bandwidth, ECC Memory and Max Memory Speed. Graphics: Integrated Graphics, Graphics Model, Graphics Base Clock, Graphics Max Clock, Execution Units, Display Outputs and Max Video Memory. Platform & Compatibility: Package and Package Size. Power & Thermals: Base Power, Maximum Turbo Power, Configurable TDP (Min), Configurable TDP (Max), Max Junction Temperature and Tcase. Physical & Manufacturing: Transistor Count, Die Size, Die Count and Foundry. Naming & Aliases: Normalized Name, SKU, Processor Number and Part Number.

Processors that use the same FCLGA4710 socket as the Intel Xeon 638 and have the closest multi-core scores in the Feex database include Intel Xeon 6724P, Intel Xeon 654, Intel Xeon 6736P, Intel Xeon 6710E and Intel Xeon 6517P.