Upcoming Ryzen 3D V-Cache CPU's in month February

Hello,

The new 3D V-Cache are coming within a month. The top line AMD CPU carries a whopping 144MB of cache. The first 3D V-Cache CPU was the 5800X3D. Although games really benefitted from the extra L3 cache, however, software applications didn’t do the same at all. I have added that review here too. Here: 3D V-Cache benchmarks

Now. I have read some on the knowledgebase of Cubase that an increase in L3 could be beneficial. Reading about Intel’s E-Cores or AMD’s SMT it can be better turned off for less complications. Also it is more important to have higher clock speeds then higher core count. The 3D V-Cache lowers the clockspeed, but adds an behemoth amount of cache memory.

Can the 3D V-Cache CPU’s be recommended in any way you think?

It really depends on the application. In some DAW use-cases there was a big benefit. The DAWbench test that some use showed a slight decrease in performance due to a slightly lower boost clock, but we’re talking about 3%, and then a pretty massive 30 and 40% uplift at 256 and 128 sample buffer sizes for how many voices could play back (those test respectively being called “DSP” and “VI” (for “virtual instrument”).

It’s a bit more complicated than that.

First of all how much you benefit from more speed or more cores depends on what you’re doing. If you have a long chain of heavy processing then you’ll want a fast core because it needs to compute things quickly. For people like me it’s different because I don’t really load up one core 100%, but I may have a lot of tracks. More tracks and more parallel processing means I can benefit more from more threads/cores.

Secondly, the Ryzen CPUs have their dies in core-complexes, the “CCX”. Each one has 8 cores. So the old 5800x3D and the new 7800x3D will both have one CCX and then the cache sits on top of that. So just the one speed there. But in order to get to 12 or 16 cores you need to have two CCX, and what AMD did was to place the cache still only on one CCX. This complicates things because if you have data in the L3 cache in CCX1 and a core in CCX2 wants that data it has to cross over to that CCX1 to get the data.

In addition to that, with two CCX and one having the cache it’s possible that you’ll see a limited clock speed on the CCX with the cache and a higher speed on the other CCX.

So there’s really no way of telling right now just how this is going to turn out on a DAW with these new 12- and 16-core chips with 3D V-Cache.

Hopefully the boost is as big as it was on the 8-core CPU with none of the speed penalty (for us), but I wouldn’t be surprised if there would have to be some tweaks either in the Windows scheduler or in Cubendo.

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Upcoming Ryzen 3D V-Cache CPU’s in month February - Cubase - Steinberg Forums