AMD Ryzen 9 5950X and 5900X Review: Zen 3 Breaks the 5 GHz Barrier

AMD Ryzen 9 5950X Boost Frequency Testing

Before we jump right into the game tests (we have the particulars of our test configurations at the end of the article), we want to highlight the vastly improved clock speeds of the Ryzen 5000 processors we've tested — with the caveat that the silicon lottery applies, so your mileage may vary. 

It appears that AMD has under-spec'd its clock rates to avoid another controversy. As per our normal routine, we put AMD's boost clocks to the test in both single- and multi-threaded workloads (methodology here). The lightly-threaded test regimen is designed to extract the highest boost clock rates possible as we step through ten iterations of the LAME encoder, then single-threaded POV-Ray and Cinebench runs, PCMark 10, and GeekBench. To keep the charts 'clean,' we only plot the maximum frequency recorded on any one core during the test. 

Image 1 of 4

We ran this series of tests at stock settings and charted the results in the first slide in the above album. Here we can see that the chip peaked at 5.05 GHz, and unlike with the Ryzen 3000 series processors, the unused cores (plotted in black) dropped to a much lower 2.2 GHz frequency (previous-gen chips tended to bottom out at 3.8 GHz). This is a vast improvement: AMD added the ability for individual idle cores to drop into sleep states quickly, which then reduces power consumption and heat generation. This ultimately allows the active cores to boost to higher frequencies, and for longer durations. 

Things got interesting when we kicked on the auto-overclocking Precision Boost Overdrive feature with the 'advanced motherboard' setting. In the second slide, we can see the chip boosted to a peak of 5.125 GHz a few times, but reached 5.0 GHz on a more consistent basis. That's incredibly impressive given the rated spec of a 4.9 GHz boost clock.  

The third slide plots our custom multi-threaded stress test that consists of multiple iterations of HandBrake, POV-Ray, Cinebench, v-ray, y-cruncher, and blender renders. This is basically throwing the heaviest real-world workloads we have in our arsenal at the chip to see if we can push any active cores below the 5950X's 3.4 GHz base clock. As you can see, the lowest clock frequency we measured on fully active cores weighed in at 3.6 GHz, which is an encouraging sign. Temperatures were also acceptable with the Corsair H115i cooler, peaking at 78C for short durations, albeit with the fans cranking away at high speed. Power consumption peaked right at the 142W PPT limit for brief periods. 

AMD has issued guidance on expected frequencies and temperatures for the Ryzen 5000 processors, which we'll include right after this series of identical tests on the Ryzen 9 5900X. 

AMD Ryzen 9 5900X Boost Frequency Testing

Image 1 of 4

Here we can see that the Ryzen 9 5900X peaks at 4.95 GHz (frequently) at stock settings, but we didn't receive as much uplift when we engaged the PBO feature. In fact, we didn't measure as many peaks during the overclocked test run, but the chip still easily exceeds its rated 4.8 GHz boost clock. 

Image 1 of 2

Naturally, lesser coolers at more mundane settings will peak at higher temperatures. To help align expectations, AMD issued the above guidelines for expected temperatures for various kinds of coolers and the expected voltage ranges for various workloads. We have plenty of our own power testing after the gaming and application benchmarks. 

Ryzen 5000 5950X and 5900X Overclocking and Test Setup

We've included our test system breakdowns below. For this round of testing, we updated to Windows 10 Pro version 2004 (build 19041.450), the most recent build available at the time of testing, and all of the benchmarks you see below were generated within the last ten days. We also updated all of our drivers, firmwares, and testing programs to the newest available versions and transitioned from the Nvidia GeForce RTX 2080 Ti to the Gigabyte GeForce RTX 3090 Eagle to reduce graphics-imposed bottlenecks. 

We didn't have time to fully explore all-core overclocking with the Ryzen 9 5950X and 5900X, but we weren't able to dial in overclocks that exceeded the all-core boost frequency. As such, we stuck with AMD's Precision Boost Overdrive (PBO), which boosts performance in multi-core workloads while maintaining the high single-core boost clocks. 

We had great results with memory overclocking with the Ryzen 9 5900X — we dialed in a 2000 MHz fabric and DDR4-4000 at a 1:1:1 fclk/uclk/mclk ratio, beating the best results we've reached with the previous-gen Matisse processors due to the general limit of a 1900 MHz fabric with the previous-gen chips. Just dial up the CCD and IOD voltage to 1.15V (not higher than 1.2V), and you should be good to go to increase the fabric clock to 2000 MHz. 

We weren't quite as lucky with the Ryzen 9 5950X, though, and settled for DDR4-3600 for our overclocked configurations below. We only ceded to the DDR4-3600 due to time constraints, though — I'm sure we can get DDR4-4000 stable with a bit more tuning. 

MORE: Best CPUs

MORE: CPU Benchmark Hierarchy

MORE: All CPUs Content