Chips and Cheese have tested the latency of the EPYC 7V73X (Milan-X) 3D V-Cache processor, AMD’s latest implementation that increases cache size.
3D V-Cache: Testing latency and bandwidth in the EPYC Milan-X
3D V-Cache technology features in the EPYC Milan-X processors, but will also be implemented in future Ryzen processor series, such as the announced Ryzen 7 5800X3D.
Performance tests show that 3D V-Cache slightly increases latency, but improves bandwidth and also increases bandwidth size. For example, the EPYC 7773X has up to three times more L3 cache (768 MB) than the EPYC 7763 (256 MB). The publication also points out that while the Milan-X has a lower clock frequency than the Milan, it has a better power supply, which would compensate for the slight increase in latency.
The 3D-V cache technology allows AMD to stack this type of memory to increase the L3 cache density. This technology is already implemented in the EPYC Milan-X and will be used in the upcoming Ryzen processors. In addition, AMD can increase the cache on each chip. For this reason, a Ryzen 7 5800X with 32 MB of L3 cache can increase its cache to 96 MB in the Ryzen 7 5800X3D model. The odd thing is that this model runs at a lower clock speed, but the performance boost from the 3D V-Cache makes up for this lack of clock speed.
The Ryzen 7 5800X3D claims that the processor achieves a 15% performance increase in gaming compared to the Ryzen 9 5900X. In the future, AMD might release a Ryzen 9 5900X3D model that could offer up to 192 MB of L3 cache thanks to this technology.
All processors based on the Zen 4 architecture will likely come with this technology out of the box, which could give AMD an advantage in certain tasks that require a lot of L3 caches, such as gaming and even blockchain. We’ll see later this year.