AMD Ryzen Threadripper 1920X & 1950X Review

Benchmarking Threadripper’s Memory Modes

Closer to the beginning of this review I mentioned that AMD implemented two different memory modes in an effort to give end users the opportunity to fine tuned their systems based on different usage scenarios. On one hand Distributed Mode prioritizes raw bandwidth while Local Mode is supposed to lower latencies by retaining memory transactions close to a controller’s associated core. In addition, the ASUS Zenith Extreme has something called “Auto” mode which isn’t really automatic at all….it simply utilizes the system default which is Distributed Mode.

But what does this all mean when the rubber hits the road? Let’s find out.

AIDA Memory Benchmarks

The AIDA memory benchmarks show exactly what AMD claimed: higher memory read bandwidth for Distributed Mode and much lower latency when NUMA is activated. Somewhat ironically, Write bandwidth isn’t touched at all.

Synthetic System Benchmarks 

As we can see, the memory subsystem setting has very little to no appreciable impact upon synthetic testing. This actually surprised me since I was expecting an application like Cinebench to take advantage of the additional bandwidth being offered but that didn’t happen. It could very well be that the 2666MHz memory speed I have set in these tests is somehow influencing differentiations.

Real World Testing

In longer real world benchmarks the Memory Mode obviously has an effect, at least in the two applications I tested. Corona sees the advantage fall to Distributed Mode while After Effects, a notorious memory hog, obviously sees some benefits with higher bandwidth.

Game Testing

Just like Distributed Mode shows net positive reactions in real world multi threaded scenarios, games obviously see benefits from the Local Mode. The uplift isn’t all that much but the results were repeatable so there is definitely some method behind AMD’s “madness”.

The question I have to pose is pretty simple: is all of this flicking of switches, reboots and other detractors from an otherwise fluid platform experience really worth a 2-3% uplift in framerates? Granted there will be outliers that benefit even more from a NUMA setup but I personally I don’t think the fuss is worthwhile. I do however have to applaud AMD for opening up this feature, I just wish it was integrated through application detection rather than direct user interaction.