AMD® Ryzen™ 9 9955HX

The AMD Ryzen 9 9955HX is a desktop processor with 16 cores and 32 threads, built on the Zen 5 architecture (4 nm process). It launched in Jan 2025. Clocks run from 2.5 GHz base to 5.4 GHz boost. A 64-MB L3 cache backs the cores (5.1 MB per core). It addresses DDR5 memory up to 96 GB across 2 channels. The chip drops into the FL1 socket and exposes PCIe 5.0 (28 lanes). Rated TDP is 55 W. Notable platform capabilities: AVX-512, AVX-VNNI, AMD-V (Hardware Virtualization), AMD SEV.

The AMD Ryzen 9 9955HX scores 4,385 in single-core performance and 55,991 in multi-core performance (PassMark CPU Mark ratings). From those two ratings Feex computes 15,669 for overall performance, 42,533 for productivity performance, 38,688 for creator performance, 64,390 for engineering performance and 27,153 for gaming performance. Its multi-core throughput works out to 3,499 per core, 1,750 per thread and 1,018 per watt. Its computed efficiency index is 2,113. Its performance index is 194, so its overall performance is 94% 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 AMD Ryzen 9 9955HX scores 212,422 in integer math, 136,552 in floating-point math, 731,307 in compression, 37,290 in cryptography, 2,722 in physics simulation, 57,886 in vector SIMD, 287 in the prime sieve and 77,836 in sorting. Higher is better. Compared with the Intel Core i5-12400, it is 261% above in integer math, 198% above in floating-point math, 221% above in compression, 225% above in cryptography, 150% above in physics simulation, 273% above in vector SIMD, 328% above in the prime sieve and 244% 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 AMD Ryzen 9 9955HX has 16 physical cores and runs 32 logical threads. It runs 2 threads per core. It runs at a base clock of 2.50 GHz and boosts up to 5.40 GHz.

The AMD Ryzen 9 9955HX is a desktop processor, belongs to the AMD Ryzen 9 family, uses the Zen 5 architecture, carries the codename Fire Range and is manufactured on a 4 nm process. It launched in Jan 2025.

The AMD Ryzen 9 9955HX has 1.25 MB of L1 cache, 16 MB of L2 cache and 64 MB of L3 cache. That adds up to about 81.3 MB of cache, or 5.08 MB per core. Each core has 1 MB of private L2 cache.

The AMD Ryzen 9 9955HX has a 3-level cache hierarchy: L1 at 1.3 MB, L2 at 16 MB and L3 at 64 MB. L3 is the largest level and makes up about 79% of the cache listed here.

The AMD Ryzen 9 9955HX supports DDR5 memory, addresses up to 96 GB of memory, uses 2 memory channels, runs memory at up to 5,600 MT/s and delivers up to 89.6 GB/s of memory bandwidth. It does not support DDR4 and LPDDR memory.

The AMD Ryzen 9 9955HX includes integrated graphics.

The AMD Ryzen 9 9955HX uses the FL1 socket, supports PCI Express 5.0 and provides up to 28 PCIe lanes.

The AMD Ryzen 9 9955HX has a rated TDP of 55 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 AMD Ryzen 9 9955HX is manufactured by TSMC.

The AMD Ryzen 9 9955HX is also identified by the model number 9955HX.

Feex has recorded 62% of the specifications it tracks for the AMD Ryzen 9 9955HX. Values Feex does not hold are shown as "Not recorded" rather than estimated.

Not recorded: Core Configuration: Efficiency Cores, Hybrid Architecture, All-Core Boost and Unlocked Multiplier. Architecture & Generation: ISA Family and Market Status. Cache: L4 Cache. Memory Support: ECC Memory. Graphics: 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 Launch Price. Naming & Aliases: SKU, Processor Number and Part Number.

Processors that use the same FL1 socket as the AMD Ryzen 9 9955HX and have the closest multi-core scores in the Feex database include AMD Ryzen 9 7945HX3D, AMD Ryzen 9 7945HX, AMD Ryzen 9 7940HX, AMD Ryzen 9 9850HX and AMD Ryzen 9 8945HX.