Cubase 10, Windows 10 and multi-core (14+ cores)

Jari Junttila…really…i dident know that. I usually let windows decides this. Maybe i should take away this viritual memory then?

As far as I know it’s better not to touch these settings and let Windows manage it.

Fabio and other Steinberg mods/devs: Any idea whether or not this might make a difference in an upcoming version of Windows 10?

“New Windows 10 update enables you to load “potentially thousands” of plugins in your DAW”

Seems like this won’t have anything to do with the MMCSS issues but at least the FLS plugin limit will be lifted, right?

There are two different problems:

FLS (Local Fiber Storage).
The next Windows Functional Upgrade will allow for about 4000 slots instead of a maximum of 128 slots.
Each plugin occupies at least one slot, but there are plugins that occupy more than four slots.

The problem of Windows 10 MMCSS (Multimedia Library).
The library has been moved from user mode to kernel mode as of Windows 10. This now limits the maximum number of virtual processors. The library is currently stable under Windows 10 Version 1809 only if the CPU has a maximum of about 14 logical processors or no more than 32 threads are occupied by MMCSS.

The second problem is not solved by the new and better FLS.
Although there should be a registration patch from Steinberg, but unfortunately the solution is only available on request and not publicly.

What Cubase 10 I do not know exactly, apparently, the program now ensures that a maximum of 32 threads are opened by MMCSS.
In my opinion, this is at the expense of performance. As long as Microsoft does not increase the maximum number of threads runs Cubase 10 with the handbrake on. (Is anyone of a different opinion?) That would mean that the performance of a 20-core CPU from Cubase when using the MMCSS only as a CPU running with 14 logical cores.

The registry patch might solve the problem, but apparently there are people who can not successfully apply the patch:

Thanks for your POV – after more research, I agree, the MMCSS issue of Cubase on Win 10 does not appear as though it will be helped by the upcoming FLS improvements of Win 10, which will mainly just benefit plugin count. But I am curious if Steinberg thinks otherwise.

As for performance improvements with the new MMCSS approach with Cubase 10, in my experience there IS a performance improvement on a 10-core (20-thread) CPU with Cubase 10 over Cubase 9.5, but more importantly the dropout/engine behavior seems improved as well. Unless I missed a bunch of posts, it seems this thread has plenty of examples of people with improvements, so I think whatever Steinberg did with MMCSS management has helped more than hurt, although there are certainly people facing issues that need to be tracked down and solved. Overall, I think it’s a step in the right direction, but I’m sure further improvements are needed.

My understanding is that the old registry tweaks, etc., are no longer needed… at least in my case they’re not needed anymore, but perhaps Fabio can enlighten us on the latest info? He mentioned various switches to control spawning prefetch threads in different ways, etc… wondering if there has been any further intel on further improvements?

Hello, I thought I’d add my recent experience with a new build. I went from a 6 core intel 64 gigs ram @ 4.5 Ghz setup to a TR 2950x 16 core 128 gig ram @ 4.0 Ghz. On a very demanding large project on the old PC with about 55 gigs of samples loaded the machine was pushed to its limits and would tip the average load meter in Cubase Pro 10 into the red a number of times where all cores/threads would be maxed out close to 100% Cpu load during playing back when viewed via the resource monitor in Windows. So I finished my new build and got it up and running and the same project was around 32 % Cpu load used in windows resource monitor but high in the average load meter in Cubase, but not tipping into the red indicator any more. It wasn’t exactly what I’d hoped for but certainly better. So I then using the Amd Ryzen Master software disabled 4 cores for a test, intern going from 16 cores down to 12 and Cubase now sits around the half way point most of the playback time over about 10 minutes which certainly achieved far better performance in Cubase 10 and more so what I’d been hoping for when I upgraded. Granted I want to take advantage of the 16 cores and not 12 but for now it’s positive results so I’m intending on doing a few more tests to try and park only 2 cores via the bios as Ryzen master needed it evenly distributed so 1 per die.

thanks for this. It’s the first real TR /Cubase 10 test I’ve seen from a user so it’s great to get some real world feedback on these CPU’s.

Keep us posted on your results.


I just bought a new system with a AMD Classico Ryzen 1920X [12x 3,50GHz] processor and Windows 10.
Can I fully take advantage of the 12 cores, or are there limitations?
Is there something in that context which I have to take care about when installing Cubase on windows 1o?

Pops and cracklings lots of real time peaks after loaded 6 synth!
I7 7820x 16gb ddr4.
Turned off C-State and Speedstep. Same result.
Cubase 8.5 run soooooo smooth.
But this version is horrible.
Not working for me so far.

Quick update – I already mentioned in this thread that my 10-core Xeon has seen an improvement with Cubase 10, but I just built a relatively affordable 8-core 9900K workstation and it works even better. To my surprise, when tested with RME USB (especially at lowest latency), it was noticeably more powerful than the older 10-core Xeon – more than I expected – and completely glitch-free with Cubase 10. Was able to push the system further and harder than any prior DAW, and it has been amazingly stable and responsive under high load. Cross fingers it stays that way! Time will tell as I get into huge projects on this system, but I’m highly optimistic and I think Cubase + 9900K may be a match made in DAW heaven. Have not tested C9.5 for comparison, but this combo seems to be – so far! – the most powerful, responsive, and stable system I have ever used for music/sound. Also huge improvements in Studio One and Reaper. Haven’t tested Pro Tools and Nuendo yet.

I think I can finally weigh in to an extent. I ended up getting the big daddy - i9-9980xe, with 16 gb ram. I’m running intensive additive synthesis so it uses a fair bit of CPU in my projects plus a fair number of VSTs. My current first test project since I set up this system is underway. I’m running right now at Cubase consuming around 40% of my CPU in Task Manager. Zero dropouts or abnormal behavior. So far this is the smoothest DAW I’ve had and I’ve been recording since the 90s. Maybe that’s because I have a monster CPU now. LOL.

I have multithreading disabled so I am essentially running an 18 core system.

I’ll update if my projects get sufficiently more complex to tax my system further or I run into any abnormal behavior.

Very interested in the i9-9980xe results!
Which CPU cooler are you using and how hot does that chip get under an intensive session?

I think you mean hyperthreading, right? I’m jealous of your setup!

I have a similar setup… it’s just a little older but with a little bit more RAM. Since you have HyperThreading disabled and a similar setup, I have a question.

When I had HyperThreading disabled, I had an unexpected side effect… the current project had no audio anymore. There is nothing reaching the Standard-Out. New projects worked as expected but the old ones don’t. As soon as HT was enabled again everything worked as expected. This audio issue is on my system reproducible and is only related to HT.

Did you (or somebody else) encounter a similar behavior when HT get’s deactivated?

As soon as I am done with this project I will also deactivate HT since the Cubase performance boost is just unbelievable!

I hope that Steinberg keeps working on the workload topic. I like working with this DAW, but the fact that Cubase 10.0.10 introduced a fix so that only 28 real time threads (14 cores) get used, is hopefully just a workaround. The ASIO-Guard is in my opinion as well a workaround related to hardware. The above mentioned performance-boost could be related to the workload preparation that is not ideal. My above mentioned Cubase 10.0.15 behavior points out that low-level workload information get stored in the project and in summary I have the impression that the Cubase workload management suffers from a legacy software architecture.

Regarding this topic I am currently not happy with Cubase, because my hardware is not fully supported,… but the good news is… there is room for improvement!

Yeah hyperthreading is what I meant. As to the other questions, I’m using a Noctua NH-C14S air cooler which fits my 4 unit rack case. It’s idling around 52°C package temp with so far up to ~50-60% CPU use and zero noticeable fan noise while the lid is on. If I take the lid off the temp drops to the high 40s. All of these are comfortable temperatures for me.

At least from my use there’s no reason to get a water cooler. Especially in a studio where you need silence this works just fine.

Regarding hyperthreading disabled - I have observed no abnormal behavior with hyperthreading disabled. I would want hyperthreading disabled regardless as some of my synths use a very large amount of CPU in a single thread and I need each thread as strong as possible.

On topic for the thread I will continue to stress my projects a bit more but I don’t think I will use much more CPU overall in any practical sense. I’d have to create a torture test project to go much higher and I don’t see the point. From what I can tell everything is working fine.

This is definitely from my experience a very good CPU for audio and it’s taken any stress of running out of CPU away from my mind. Most people will never need this much CPU ever for any reason. I will update if I run into any trouble.

fwiw, I have the 7900x running all 10 cores at 4.3 ghz, and I have noticed that hyperthreading is actually pretty effective in Cubase 10. I tried disabling it, and it appears to drastically increase CPU load and “average load” in the ASIO monitor. With hyperthreading on, the cpu load is lower and it seems to have a lot more headroom, and is utilizing the threads in such a way that it’s acting sort of like 20 cores.

I keep hyperthreading on because it actually seems to benefit cubase 10 in my experience. Granted, these are just test sessions and I haven’t tried a massive project yet. The results of that have yet to be seen.

This is strange… that is the exact opposite experience of mine. I try to find a pattern but the only difference I see so far is that you have less than 14 cores… but does that really matter that much?

I hope you can test it on a normal project and that you post your experience.

Hyperthreading should be On.
If that somehow decreases performance, then something somewhere is wrong.
From my own tests and from what I can read on some of the more well known DAW computer manufacturers. A gain in performance around 40% up to 70% is not uncommon.
I would be looking at bios updates, drivers or even a fresh OS install if I had worse performance with Hyperthreading ON.

Hyperthreading should be On.
If that somehow decreases performance, then something somewhere is wrong.

Unfortunately, it’s not so simple. It depends on what you understand for “better performance”. If you disable Hyperthreading you give more time to the different cores to synchronize their threads, so it’s very likely that you get better ASIO performance (less clicks) at very low latencies, especially when playing VST instruments. However, if you’re at the mixing stage and higher latencies aren’t a problem, then yes, Hyperthreading can give you a boost in performance, usually no more than 20% in my experience.

Yes if you want to run at extremely low latency, HT off might get you room for a few more vst instruments.
But then I would suggest a low latency audio card like a RME would make a bigger impact.