So with Windows and Cubase 9.5 and Nuendo 8, there is a problem with 14+ logical cores with MMCSS management, and it can cause dropouts in certain conditions. That means any machine with an Intel 8-core CPU or better (Intel 8-core CPUs such as the 9900k obviously have 16 logical cores with hyperthreading enabled), you will have these potential problems. So in order for Cubase 9.5 (and earlier) and Nuendo 8 (and earlier) to run well on those machines, there are some specific tweaks that you can get from Fabio (of Steinberg). There are actually a few other approaches that I don’t personally recommend from my own testing… I have found Fabio’s tweaks to be the best… but you could, for example, not use Fabio’s tweaks and just disable hyperthreading, or disable cores, etc., etc… but Fabio has another method that has been better in my testing.
Now with Cubase 10, they introduced a NEW MMCSS thread management system that has been quite good in my testing and it does NOT require any of the old tweaks (and it does NOT require disabling any of your cores, it does NOT require disabling hyperthreading, etc…). In my experience, the new Cubase 10 engine runs noticeably better on both my 10-core (20 logical) and 8-core (16 logical) systems. Even at really low latencies. I’ve tested Cubase 10 with RME at lowest settings with all cores enabled, hyperthreading enabled on my 9900k for example, and it works buttery smooth, with VERY heavy load and massive projects.
So if someone is getting great performance with Nuendo 8 on a 9900k, then:
- they are NOT using Nuendo 8 on projects that create the conditions where the MMCSS thread problems will cause dropouts, for some reason… but I believe they will eventually run into the problem under high load. I’ve tested this extensively with my 10-core system and definitely needed help from Fabio to get Nuendo running optimally…
- they have disabled hyperthreading
- they have disabled one or more cores
- they have applied some tweaks (preferably from Fabio!)
- they have not noticed dropouts yet (see reason #1)
- there is some other mystery going on and who knows, they might have found a magic unicorn configuration and that would be wonderful for all of us
In any case, Nuendo 9 will have the updated MMCSS thread management of Cubase 10, and this problem will hopefully be put to rest. I understand that the engine improvements are a work in progress, so we’ll see continued improvements with thread management in future updates… but Cubase 10/Nuendo 9 are a good step forward.
Hope that helps.
For more info, check out this thread and reach out to Fabio, who seems to be the gateway at Steinberg for this info: