AMD Ryzen 9 5900X vs Ryzen 9 3900X Performance Review

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AMD Ryzen 9 3900X CPU side by side Ryzen 9 5900X CPU Banner


Today we are going to directly compare performance between the AMD Ryzen 9 3900X CPU known as Matisse and the AMD Ryzen 9 5900X CPU known as Vermeer. This is Zen 2 versus Zen 3, head-to-head 12-core to 12-core in the high-end desktop (HEDT) performance PC enthusiast realm for CPUs. In addition, we are also throwing in the Intel Core i9-11900K to see how these three CPUs compare to each other. We are going to find out what upgrading from Ryzen 9 3900X to Ryzen 9 5900X really brings to performance generation to generation, and also see how Intel’s Rocket Lake-S 11th Gen enthusiast CPU fits into all of this.

AMD’s Ryzen 9 5900X was originally released about a year ago, in November of 2020, though availability was scarce for a while after launch. It was much the same situation we’ve seen with graphics cards and price gouging, scalping, and everything else that’s made the news. These days the Ryzen 5000 series CPUs are much easier to get. While most people buy somewhere around the midrange, many people would argue that the Ryzen 9 5900X remains the “sweet spot” at the top as it’s considerably cheaper than the Ryzen 9 5950X, while providing the same performance for most people.

Since it has been a full year since its release, it’s a great time to revisit performance on the Ryzen 9 5900X. Since its launch, many new BIOS updates and AMD AGESA updates have been made, including chipset driver updates and driver and stability updates in general. Basically, the Ryzen 9 5900X is going to perform today at the peak of its ability. Today, we’ll be looking at the Ryzen 9 5900X’s performance and comparing it to various CPU’s including its direct predecessor.

AMD Ryzen 9 5900X Specifications

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AMD Ryzen 9 5900X spec slide

The Ryzen 9 5900X is a 12 core 24 thread CPU based on the Zen 3 architecture. The Ryzen 9 5900X has 64MB of L3 cache and 6MB of L2 cache. It has a base clock of 3.7GHz and a maximum boost clock of 4.8GHz. On the surface, the CPU’s specifications are virtually identical to that of its predecessor excluding the base clock, which has gone up 200MHz for both the base and maximum boost clock values.

Otherwise, all of the differences between the Ryzen 9 3900X and the 5900X mostly come down to their architectures. The former being Zen 2, the latter being Zen 3. For the sake of brevity, we will not be regurgitating the inner workings of the processor architecture in this review. For more information on the improvements to the Zen3 microarchitecture, you can read our coverage on the topic here.

SpecificationRyzen 9 5900XRyzen 9 3900X
ArchitectureZen 3 / VermeerZen 2 / Matisse
Process Node7nm CCD/12nm IOD7nm CCD/12nm IOD
L2+L3 Cache6MB L2/64MB L36MB L2/64MB L3
Base Frequency3.7GHz3.8GHz
Max Boost Frequency4.8GHz4.6GHz

One of the improvements to the architecture I will mention is the CCD / CCX complex reconfiguration. The earlier 3900X CPU had two CCDs utilizing four CCX complexes each. Each CCX complex had three cores instead of four. The newer CCD configuration means reduced latency internally which was one of the issues with the previous generation Ryzen CPU’s in certain applications. Primarily, games were sensitive to crossing the CCX boundaries inside each CCD. This isn’t a problem anymore in Zen 3 based CPU’s which no longer have CCX boundaries for data to traverse.

The Ryzen 9 5900X still has two CCDs like its predecessor. Again, there are only six cores per CCD instead of eight as we would see with the Ryzen 9 3950X or 5950X. Interestingly, the Ryzen 9 5900X has been around long enough to have to compete with Intel’s Core i9 10900K, 11900K, and now, the 12900K.

Packaging & Installation

The packaging of the Ryzen 9 5900X is identical to that of earlier CPUs with minimal changes to the package artwork. However, unlike the 3900X, it does not come with a CPU thermal solution and as a result, the packaging is like that of the Ryzen 9 3950X in terms of size rather than the 3900X which still came with a heat sink and fan. In terms of value, a lot of people felt cheated by the lack of a thermal solution being provided with this CPU. However, AMD’s solution wasn’t really ideal for the 3900X and was practically a no-go for the 3950X. Sure, you could use it but you were likely leaving some performance on the table by opting to use it over a good AIO or at least an aftermarket high-end air cooler.

Given that the Ryzen 5000 series CPU’s utilize AMD’s socket AM4, there are pins on the bottom of the socket. The socket on the motherboard is a zero insertion force style socket and installation is fairly straightforward with the pin array on the CPU denoted with a mark to indicate where pin one is. There is a corresponding mark on the socket and the CPU, when aligned properly should fall into place with no force being required to seat the CPU. Once in place, close the locking lever and all you need is your thermal solution. For that, you’ll want to refer to the manufacturer’s instructions for whatever you are going to use for cooling.

Essentially, there is nothing different or odd about installing your Ryzen 9 5900X CPU. The only caveat to this is that you will probably need to flash the BIOS of your motherboard prior to installing the actual CPU. There are some motherboards that do have the ability to update the BIOS without having the CPU installed but these are typically among the more expensive offerings out there. The motherboard used for our testing here was the ASRock X570 CREATOR, which required flashing with a Ryzen 3000 series CPU (or older) installed.

Aside from that one hiccup, there were no other issues to note when installing the 5900X CPU into our test system. Sometimes the BIOS has to be tweaked on some systems for things to work properly, but that wasn’t the case here.

CPU Frequencies

As stated earlier, Ryzen CPUs essentially have a base clock frequency and then a maximum boost clock frequency. The former is a minimum clock speed you can expect provided that thermal conditions are right and the CPU is at full load. When idle, the clocks can drop dramatically in order to save power which is normal for any modern CPU.

However, with single-threaded or lightly threaded workloads, the maximum boost frequency of 4.8GHz is technically possible on a single core. You can also see frequencies that exceed the base clock by a large margin when the CPU is performing heavily multithreaded tasks. In those cases, seeing speeds in excess of 4.0GHz is likely. Though the ceiling on that will fall short of the 4.8GHz maximum boost clock frequency.

Anything in between the base clock and the maximum rated boost clock depends entirely on several variables which include workload, temperature, and voltage conditions to put it simply. You can see clock speeds anywhere in between the base clock and maximum rated boost clock frequencies.

Dan Dobrowolski
Dan has been writing motherboard reviews for the past 15 years, with the first decade or so writing for [H}ard|OCP. Dan brings his depth of knowledge about motherboards and their components to his reviews here at The FPS Review to help you select the best one for your needs.

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