The AMD Ryzen 9 9955HX is a mobile processor with 16 cores, launched in January 2025. It is part of the Ryzen 9 lineup, using the Zen 5 (Fire Range) architecture with Socket FL1. Thanks to AMD Simultaneous Multithreading (SMT) the core-count is effectively doubled, to 32 threads. Ryzen 9 9955HX has 64 MB of L3 cache and operates at 2.5 GHz by default, but can boost up to 5.4 GHz, depending on the workload. AMD is building the Ryzen 9 9955HX on a 4 nm production process using 16,630 million transistors. The silicon die of the chip is not fabricated at AMD, but at the foundry of TSMC. You may freely adjust the unlocked multiplier on Ryzen 9 9955HX, which simplifies overclocking greatly, as you can easily dial in any overclocking frequency.
With a TDP of 55 W, the Ryzen 9 9955HX consumes typical power levels for a modern PC. AMD's processor supports DDR5 memory with a dual-channel interface. The highest officially supported memory speed is 5600 MT/s. ECC memory is supported, too, which is an important capability for mission-critical systems, to avoid data corruption. For communication with other components in the machine, Ryzen 9 9955HX uses a PCI-Express Gen 5 connection. This processor features the Radeon 610M integrated graphics solution.
Hardware virtualization is available on the Ryzen 9 9955HX, which greatly improves virtual machine performance. Programs using Advanced Vector Extensions (AVX) will run on this processor, boosting performance for calculation-heavy applications. Besides AVX, AMD has added support for the newer AVX2 and AVX-512 instructions, too.