RealityCapture CPU Performance: AMD Ryzen 9 3950X

Introduction

AMD's new Ryzen 3rd generation processors feature both an increase in core count and per-core performance, allowing them to rival Intel's mainstream Core processors in many professional applications. The first chips in this series did well with RealityCapture in our previous testing but didn't quite beat Intel's Core i9 9900K, so now we are going to see how the top-end Ryzen 9 3950X fares.

RealityCapture, like other photogrammetry applications, is built to take a batch of photographs and turn them into digital, 3D models. Many steps are involved in that process, utilizing both the CPU and GPU at different points. Our focus here is on CPU performance, so most of the other hardware in the test systems will be fixed, but we will also look at two different RAM speeds for AMD's Ryzen chips.

Test Hardware

Since this article is focusing on the new Ryzen 9 3950X, which is the top-end of AMD's mainstream processor family, we wanted to let it face off against a few of AMD and Intel's similarly positioned CPUs along with some other 16-core chips from higher-tier product lines.

A complicating factor is memory speed support, though: most processors on the market today officially support up to 2666MHz memory, while these 3rd gen Ryzen chips are rated for different maximum memory speeds depending on how many RAM modules are installed. The spread goes from 2666MHz up to 3200MHz (if only using two modules) – but that limit would mean less total memory capacity, which could impact some of our benchmarks. Because of that, I decided to test the Ryzen processors at both ends: with a full set of four 16GB modules at both 2666 and 3200MHz, even though that is technically outside the supported range. We can't sell systems configured that way, because we need to stick to AMD's supported specs, but by having the performance data from both ends of the spectrum we can give our customers a good idea of the rough range they'll end up in. All other CPUs were also tested with 64GB.

Benchmark Details

For testing photogrammetry applications, we have four image sets that we own the rights to – covering both smaller and larger size model and map projects. The smaller image sets are included in our public RealityCapture benchmark, which you can download and run if you want to compare your system's performance to what we measured in our testing.

• Rock Model – 45 photos at 20 megapixels each
• School Map – 51 photos at 18 megapixels each
• School Model – 278 photos at 18 megapixels each
• Park Map – 758 photos at 18 megapixels each

Each image set was processed 3 times on each CPU, and the fastest overall result was used for the comparisons below.

Results Overview

Here is a gallery of charts for each of the four image sets, showing the total time (in seconds) they took to process on each CPU.

A note about the color-coding used here: AMD processors are shown in orange with 2666MHz memory and red with 3200MHz – which is out of AMD's official supported specs at this capacity and speed combination – while all Intel processors are shown in blue.

Detailed Results

For those who want to dig further into the differences in how each CPU performed, here is a table showing the times for each step within RealityCapture on each of the image sets:

Analysis

AMD has pulled out a win here, taking a solid lead over Intel's processors in RealityCapture! The new Ryzen 9 3950X was always faster than the Core i9 9900K in our tests when equipped with 3200MHz memory (though that means either limiting yourself to 32GB currently or else going outside of AMD's official memory support for this CPU). Even when using 2666MHz memory, it only placed behind the 9900K on our smallest image set – and that was by less than 1%, potentially within the margin of error.

On larger projects, even the Ryzen 9 3900X placed ahead of Intel's processors… which is a slightly different story than we saw the last time we looked at RealityCapture performance. Since then there have been updates to Windows 10, NVIDIA drivers, RealityCapture, and motherboard BIOS – any or all of which could have impacted performance. In fact, it looks like performance is better across the board… most likely due to the newer RealityCapture version. The 9900K is still a solid processor for this workload, just not the top dog anymore.

Moving on to memory speed, on the Ryzen platform, there is about a 3-5% difference in overall RealityCapture performance when using 3200MHz memory versus 2666MHz. Unfortunately, sticking to AMD's official supported memory specs means that you could only get 32GB with the higher speed – since 3200MHz is only supported with just two memory modules – but this fairly small performance delta means that you can get more RAM (which is often important for photogrammetry) without taking too big of a hit on processing time.

Here at Puget Systems, in the long run, I suspect we will end up settling on 2933MHz. That should offer slightly better performance than 2666MHz while also allowing the use of a full four memory modules. RealityCapture is impacted by RAM capacity, at least on larger image sets, so keep AMD's official memory support specs in mind if you are configuring a Ryzen workstation.

Conclusion

AMD's new Ryzen 3950X is the clear performance winner for RealityCapture, at least among the chips we tested. Intel and AMD both have more processing coming out in the near future, so that may be subject to change, but for now AMD has taken the lead here.