So what is the most powerful (but stable!) CPU to use with Cubase?

I was planning on doing a 7900x build, but now I’m reading the horror stories about how Cubase doesn’t work right with more than 14 cores. So what is the most powerful build we can currently do on a PC? The 8700k? Thanks!

I’m using a 7900x limited to either 8 or 10 cores and it’s working wonderfully. Easily will run at 4.3gHz while staying very cool with a quiet Noctua air cooler, although even at the stock 3.3gHz it handles large Cubase templates with less than 10% CPU. I haven’t heard an audio glitch or seen a Performance Meter red line since I got things sorted out with the hardware and software setup. The issues people have reported are due to very conservative default settings in BIOS setups which leave the CPU stupidly at the mercy of issues coming from video drivers, needlessly low idle clock rates, etc.

That being said, the 8700 would be a fine choice for systems running Cubase only, I don’t think you would see any performance advantage or disadvantage versus a 7900. What I’m doing is concurrently running Cubase with various video editing packages and in that way the 7900’s large core count buys a lot of worthwhile capacity. Also, the 7900 is absolutely the first choice for systems intended for 3D graphics or high resolution video editing. FWIW If you go with the 8700 be sure your motherboard can accept more than 64gb of RAM, some can’t and that is starting to be a limitation for those working with newer, large sample libraries and is seriously limiting for high resolution video.

Hi Bill. I was hoping you would reply. Is there a reason you limited to 8 or 10 cores and not 14 cores? I love that idea of being able to have some extra cores to put toward video work, as I could see myself regularly doing some simultaneous video recording for tutorials, etc. I saw on another post you really got in and figured out which specific cores were needed, etc. Any hint on how you did that? Do you use that script that Steinberg provided to limit the cores or doing it by turning off hyperthreading?

Lastly, any chance you are using a a thunderbolt interface? I use an Apollo 16, and I’m wanting to build this to be able to use thunderbolt instead of my old firewire setup.

Read the official statement more closely. It doesn’t say you can’t run Cubase with over 14 cores, it says you might run into glitches with more than 14 logical cores (i.e. >7 physical cores). That’s what I recall it says actually.

In addition to that people are running octa cores and above without problems, so it doesn’t seem to affect all users in all circumstances.

Thanks I did read the statement. There is also a many-page long thread on the Cubase thread with a whole lot of people that are dealing with this issue, so before I spend $4000 building a new computer, I want to hear from people who have a working system and what they did to make it work.

Bill mentions here and in the other thread that he limited his logical cores to 10. Matthias do you have a system with more thank 14 cores that you are running at lower latencies with no issues?

BTW the statement says "processing threads exceeding this amount will be carried out as non-real-time (like UI-threads), introducing drop-outs and performance issues.

So that sounds a lot more final than how you are portraying it.

Hi mbira,

I’m using 8 or 10 cores because that’s more than enough for DAWs, but mainly because those core counts seem to shift the Nvidia nnvlddmkm.sys interrupt up to a higher core number that is not being used by Cubase. That Nvidia interrupt is the most obtrusive one on the system. When I started looking at these issues it was occurring on core 0, but for some reason it has since obligingly moved itself up to core 10 (which is the eleventh core if you count from 1 instead of 0), which is not used by Cubase. I can’t tell you exactly why, by I am ever grateful for this.

You can get good insight into your cpu core usage with the free “LatencyMon” program available from The “Main” tab shows you the 4 biggest system-hog interrupts (usually includes the ndis.sys network driver and Nvidia’s nvlddkm.sys driver). The “CPUs” tab shows more information. Keep in mind that LatencyMon itself uses a lot of resoruces, so your actual numbers may be a little better than it reports and it may glitch DAWs on some systems.

Steinberg suggests limiting the cores available to Cubase through placing a script file in the Cubase appdata directory, I prefer to do so using a customised shortcut icon on my taskbar at the bottom of the screen. Like this…

  1. Right click the Cubase icon
  2. Right the Cubase icon that pops up (labelled Cubase 9.5)
  3. Left click Properties
  4. Delete what’s there in the “Target” biox and (assuming you have the default Cubase file structure on your computer) substitute:

C:\Windows\System32\cmd.exe /c start “Cubase 9.5_64.exe” /affinity 3FF “C:\Program Files\Steinberg\Cubase 9.5\Cubase 9.5_64.exe”

Reality check…I’m not at that computer so I’m recalling that command line from memory. I pretty sure it’s right, but maybe you should compare it to what’s in the box initially. Also, that assumes you are using the default Steinberg installation directory scheme.

That gives Cubase ten cores. “FF” gives 8, “3F” gives 6, “F” gives 4. Those all start from core 0, Cubase seems to require core 0 be on the list. Of course this only works if I launch Cubase through that particular shortcut icon. In theory you could have multiple “rigged” shortcuts for various numbers of cores depending on what else you want to run simultaneously.

To verify, run Task Manager, left click the “Details” tab, right click “Cubase”, left click “Set Affinity”, and you will see a list of cores that Cubase is using. At that point you can theoretically change the affinity list by clicking those boxes, but that will crash Cubase, so don’t do it.

You can monitor ongoing CPU performance with “CPUID HW Monitor” which is also free. Reports CPU temps as well, so it’s useful if you want to overclock. With that big Noctua heatsink and just one of the two fans running, my i9 doesn’t actually get anywhere near as hot as the hype suggests, even at 4.3gHz where it idles at 42C and never hits 68C. I normally run at 3.5gHz (36C idle), it’s a nice sounding number and more than adequate. It was through CPUID that I found that when I gave Kontakt four CPUs, it was sharing 0…3 with Cubase with not very much impact at all for the sample-intensive VST instruments I use.

I’m still looking at the effect of DaVinci Resolve, but it seems that even without a core-specifying shortcut it shares cores very nicely with Cubase, and makes a lot of use of cores 11 to 19. DaVinci is known to be lurchy playing back many consumer video formats in native format, but even with uncoverted GH4 and GH5 files it flows very nicely alongside Cubase.

Also, be sure to prevent the i9 from idling below 3.3gHz, there is almost zero heat dissipation penatlty for doing that and it is super vulnerable to the Nvidia and networks interrupts at my BIOS’s default 1.2gHz idle speed.

Sorry, no Thunderbolt stuff here, although my Asus TUF Mark II has an optional Thunderbolt accessory card and the middling-sized PCI slot to go with it.

Would be nice if there was some way to tempo-sync Cubase and DaVinci, maybe some day. Open loop is still way better than inflexible work prints.

Bill-excellent post. Thanks so much for the detail. Great also to hear that the air cooling is working well for you. It’s true that the internet is full of horror stories. I’m planning on a basic AiO water cooling system so I should be good to go. I tend to really push my system to its knees when I’m at the mixing stage, so it will be great to get a little more headroom there.

It’s still wrong though. If it was a correct statement then anyone running more than 14 logical cores would get “drop-outs”. That’s not the case, so the statement is incorrect.

For reference:


Since some people are getting problems however the correct phrasing should be that you might get “drop-outs”. But you are correct, the official doc by Steinberg says what you say it does, it’s just that it apparently doesn’t work out that way always.

You can look at my sig for my system specs. I ran DAWbench DSP tests on it and the non-VI test with ASIO-Guard ON gave me so many plugins I stopped the test without maxxing It out. With ASIO-Guard OFF I got far fewer, but still enough once latency was increased.

So again: It’s possible to run Nuendo (and thus probably also Cubase) with 14+ logical cores and not have a problem, and it’s also possible to have a problem.

Here are my test results:

First you tell me to read the statement closer, and now you are telling me the statement is incorrect? You make it hard to keep up, man.

I’m glad to hear that your ryzen system is working well for you and that you are not having issues with drop outs! So you are successfully getting all 16 cores of your ryzen working in Nuendo at low (64) latency?

Not really that hard. I told you to read the statement closer, and apparently I remembered it differently. Like I said, if it’s as clear-cut as it indeed seems then I and others would have “drop-outs”. If we don’t then the statement isn’t correct.

If you read the post I linked to it says:

DAWbench, RXC-EXT results:

Buffer: 32 samples
RXC-EXT: 213 instances

Buffer: 32 samples
RXC-EXT: 320+ instances (end of DAWbench tracks)
ASIO-Guard: ON

Buffer: 128 samples
RXC-EXT: 256 instances

Buffer: 256 samples
RXC-EXT: 294 instances

Those were the limits for those settings. So, with AG off at 64 samples I would expect between 213 and 256 instances of the RXC-EXT plugin. More importantly (for me), with AG on I got far more plugins than I normally need, and I’d expect to get far more if I kept going, so I just stopped. Mind you I don’t do any VI work so latency isn’t that important to me. 128 or 256 is more than fine. Probably 512 as well.