AMD Ryzen 9 3900XT, Ryzen 7 3800XT and Ryzen 5 3600XT Review: Small Gains, Big Price

[harlan4096]

Ryzen XT underwhelms
 

Our Verdict

AMD's Ryzen 9 3900XT brings improvements to lightly- and mid-threaded performance to bear, but the gains are minor enough in most applications that it isn't worth the high price and associated cost of an aftermarket cooler, especially in light of the value of AMD's own X-series processors.

For

• Improved single-threaded performance
  
• Improved mid-threaded performance
  
• Support for PCIe 4.0
  

Against

• High price relative to X-series models
  
• No bundled cooler
  
• Small performance gains in the majority of applications
  

AMD's new Ryzen XT lineup comes as a refresh that's designed to tackle Intel's new Comet Lake processors. The XT family brings three new flagships to bear:

The Ryzen 9 3900XT, the Ryzen 7 3800XT, and the Ryzen 5 3600XT that will all vie for a spot on our list of Best CPUs. Surprisingly, on the surface, the XT lineup looks a lot like what we've seen in the past from Intel: An iterative lineup of chips with small differentiation from their predecessors in terms of features and clock speeds, not to mention the same number of cores, same process node/density (albeit with some refinements), and the same microarchitecture as their predecessors.

AMD even eliminated bundled coolers from two of its three new models, which runs counter to its standard value proposition of throwing in all the goods with each chip. Overall, the Ryzen XT series doesn't appear to have the explosive gains like we're used to with AMD's gen-on-gen improvements, but there's a lot more nuance to the XT story than what we see on the spec sheet. 

XT Series RCP (MSRP) Cores / Threads Base / Boost GHz TDP L3 Cache

---

Ryzen 9 3900XT $499 12 / 24 3.8 / 4.7 105W 64MB
Ryzen 9 3900X $499 / $434 12 / 24 3.8 / 4.6 105W 64MB
Ryzen 7 3800XT $399 8 / 16 3.9 / 4.7 105W 32MB
Ryzen 7 3800X $399 / $339 8 / 16 3.9 / 4.5 105W 32MB
Ryzen 5 3600XT $249 6 / 12 3.8 / 4.5 95W 32MB
Ryzen 5 3600X $249 / $205 6 / 12 3.8 / 4.4 95W 32MB

A quick glance at the spec sheet shows most of the key specifications remain unchanged, with the most substantial change being that the 12-core 3900XT comes with a 100 MHz higher boost, the 8-core Ryzen 7 3800X gains 200 MHz, and the 6-core Ryzen 5 3600XT gains 100 MHz.

Due to refinements to the 7nm node, AMD says it improved boost frequencies by 2-4%, but it also improved boost residency, or how long the processor remains at its boost frequency, by up to 80%. Combined with the incrementally higher clock speeds, AMD says the improved boost residency improves lightly-threaded performance by 4-5%.

As we'll cover below, the minor increases to boost frequencies that we see on the spec sheet don't take into account that the processors now have more room to boost higher in mid-threaded workloads (those that don't fully saturate all of the cores). That capability delivers up to 10% more performance in some workloads, but we found those are pretty rare. AMD wrung out this extra performance while leaving key power limitations unchanged, meaning you get more performance within the same maximum power envelope. 

We also see some gains in gaming performance, albeit not of the explosive sort. AMD says you can expect about a 2% improvement with the 3900XT and a 4-5% improvement with the 3800XT, depending on the title. We didn't see as much uplift, though. As expected, games that respond to lightly-threaded performance benefit the most, so gains can be scattered. 

AMD advises that these processors aren't meant to be a direct upgrade path from existing Ryzen 3000 processors. Instead, the existing chips will still be available at retail. The new XT-branded chips will serve as another choice for customers if they're upgrading to a Ryzen processor for the first time, or refreshing an older rig. 

You'll need to bring your own 280mm (or greater) AIO liquid cooler for Ryzen XT 9 and 7 chips, though, which adds to the pricing significantly. We did record slightly improved performance from the auto-overclocking PBO feature over prior-gen models, but AMD also says you shouldn't expect higher manual overclocking frequencies from the new chips. 

Overall the Ryzen XT processors offer incremental performance increases in gaming that aren't worth a direct upgrade, and most gamers are better suited with either AMD's existing models or Intel's competing chips – The Ryzen XT series doesn't change the gaming landscape much. If gaming is your primary focus, you'll be better served with less expensive Ryzen alternatives, like the Ryzen 7 3700X or the Ryzen 5 3600X. The Core i5-10600K is another solid choice that leads our list of Best CPUs.

Due to the performance characteristics of the XT models, they're a decent step up over the standard models if you frequently use productivity applications that aren't exclusively heavily-threaded. The Ryzen 9 3900XT and Ryzen 7 3800XT, in particular, deliver great gains in a few productivity apps, like Photoshop and Adobe Premier, so paying a bit extra for the chip only makes sense if you already plan on using an aftermarket cooler and use those types of apps almost exclusively. 
...

Continue Reading