Introduction

The new Ryzen 9 7900X launches alongside AMD's first wave of next-generation "Zen 4" desktop processors. With their new architecture, AMD isn't just future-ready with new I/O, but also its applications, with support for new instruction-sets. The 7900X is a 12-core/24-thread conventional multi-core processor which software doesn't need special awareness for. It is being positioned to compete with both the Core i7-12700K and the top i9-12900K, since all twelve of its cores are what Intel would call "performance" cores. Zen 4 is designed to offer a 13% IPC uplift, which when paired with high clock speeds north of the 5 GHz-mark, translate into a 44 percent multi-threaded gain, AMD claims. This means that in creator workloads that scale across all cores, the 7900X should overcome its core-count deficit, and offer performance matching the 16-core 5950X "Zen 3," at a lower price-point, and on a future-proof platform.



The Ryzen 9 7900X is squarely a creator's processor for those who don't want to spend too much on the CPU. Not only do you get 12 "Zen 4" cores, but also next-generation I/O that includes DDR5 memory and PCI-Express Gen 5. AMD's implementation of the latter goes a step further than Intel's—you get Gen 5 not just with the x16 PEG slot, but also two additional x4 interfaces, besides the chipset-bus. It's possible for motherboard designers to wire these out into two Gen 5 M.2 NVMe slots without eating into the x16 PEG, , or deploy high-bandwidth onboard devices, such as future discrete USB4 controllers with 80 Gbps bandwidth per port; Thunderbolt 4, etc. The processor itself puts out 20 Gbps USB 3.2 connections, and if you opt for chipsets such as the X670E, you get a wealth of USB 3.2 connectivity, besides Gen 4 PCIe downstream connectivity.

AMD carved the Ryzen 9 7900X out of the same dual-CCD configuration of "Raphael" as the top 7950X, by disabling two cores per CCD. This means that there are six "Zen 4" cores per CCD, each with 1 MB of dedicated cache, and a massive 32 MB of shared L3 cache per chiplet (mathematically 5.3 MB per core). The 7900X is clocked at 4.70 GHz base, with an impressive 5.60 GHz boost frequency. The processor comes with the same 170 W TDP and 230 W PPT power limits as the 7950X, with fewer cores to distribute that power among, which means better boost frequency residency. AMD is unambiguous about the need for at least a 240 mm or 280 mm aftermarket AIO liquid CPU cooler to go with the 7900X; the good news is that the new Socket AM5 is cooler-compatible with AM4, which means you have plenty of choice.

There are two key feature-additions to the Ryzen 7000 series that were long overdue, and which could sweeten the deal for the 7900X. First, is the inclusion of integrated graphics. The playing field with Intel is now leveled, and all those who want these chips just for their processing power, and don't need graphics cards; will get an iGPU that's as capable as the ones Intel includes with its Core i9 desktop processors. The second feature that should appeal particularly to the AI deep-learning crowd, is the addition of AVX-512, VNNI, and BFLOAT16 instruction-sets. AMD's implementation of AVX-512 doesn't come with additional power-overhead, and won't result in lower clock-speeds to reduce head/power-draw when running code that uses it.

AMD is pricing the Ryzen 9 7900X at $550, or exactly halfway between the $400 7700X 8-core, and the $700 7950X 16-core. Its core-count is halfway, too. In this review, we put it through its paces on our brand new test-bench, to which we've added dozens of new benchmarks and game-tests. We've rebenched every single processor you see in this review, and our selection of processors goes all the way back to the very first generation of Ryzen, and competing Intel processors from that time, so you know if your high-end setup from 5 years ago needs an overhaul.