Finding the ASIO Bottleneck

Greetings all,

I have recently upgraded to Cubase 9.5 and just started looking at optimising my system for it. I am using the following hardware:

Intel 4790K CPU (4Ghz)
32GB Corsair RAM
Asus Z97P Mobo
Various SSD drives
EVGA NVidia GTX960
Focusrite Scarlet 18i 20

Running windows 10 - 64bit
Avast Anti Virus
Latest bios and drivers for everything as far as i know.

The issue I am having is that the ASIO performance bar is maxing out when the actual resources on the system are pretty low. The CPU, RAM and Disk usage are all way less than 50% - yet ASIO is maxed.

I have gone through a couple of guides I found in the forums here to check BIOS options for CPU / Power functions, but changing them only made a minimal difference. I can see in the process monitor in windows that none of the individual logical cores are maxed out (all under 50%).

I have set the buffer to maximum for the ASIO driver for the focusrite card too.

Anyone know how to more accurately discern where the bottleneck is? I don’t have any other soundcards to test with the machine unfortunately.

Thanks in advance

Read through this thread as we are discussing the same problem there

Thanks - I had seen that thread already, yes. I have now used Latencymon to analyse the realtime performance of the system and the only visible issue is that an nvidia process sometimes goes above 1ms latency when Cubase is maxing out on the ASIO. I have tried completely removing the Nvidia driver and also using an older driver, but it made no beneficial difference.
I’m not sure if the Nvidia card is actually part of the issue or not - I have seen others saying that they have problems with Nvidia cards and Cubase. I am thinking of replacing the card anyway, but I have no idea how I would know what would be a better card to get (that can also handle games, 3D rendering, photo editing and video editing well).

First… check this out if you haven’t seen it…

I have a Nvidia 960. It now works perfectly with no issues at all. I always run with the latest driver. I had some issues a few (probably) years ago. What I did was to do a custom driver install. Choosing the clean install option that pops up during the advanced custom install. Uncheck all other Nvidia software so that the clean install uninstalls these unnecessary programs. Make sure to scroll down to uncheck them all.

Unrelated to bottneck (maybe)… the older Nvidia graphics driver install package used to install GBs worth of temporary files on your harddrive. And it did this every time you installed a new driver. So make sure to look for those older folders/files and trash them all. Literally many GBs of space is wasted by these “temporary” files that did not auto uninstall. They will most likely be found in a folder that gets installed at the default Nvidia location on the c drive. FYI… the newer driver install packages auto deletes these newly installed temporary files

Back on topic… I also uninstalled the HD Realtek driver from my motherboard keeping only the regular Realtek driver for PC sound.

Also… I disabled the Intel video on my MB.

Also… I trashed my 3rd party antivirus software years ago and only use the one from Microsoft. It works fine.

Hope the vid above helps.

Regards. :sunglasses:

First, I like to check how the performance is with just 1 or 2 Vst in an empty project. Is that already consuming a lot (like more than 30%)? If it is then you should probably focus your effort on bios/ windows setup.

ASIO bottleneck is typically CPU (for math intensive), or RAM (for RAM intensive). That is why overclocking is so common for mobo’s that support easy overclocking (ie. OC on air)


It’s a common misconception to assume that every vst uses the same amount of resources. Testing your system with 2 instances of Retrologue that use just one oscillator generating a sine wave as apposed to 2 multies with granular synthesis in Omnisphere is to say the least false. It’s like saying “I just tested my health by running a kilometer with two completely filled up backpacks. The main question is: what did you use to fill up those backpacks? Feathers or lead?!”

Tunist, Go to Studio > Studio Setup and to VST audio system and enable the following:

  • Activate Multi Processing
  • Activate Asio-Guard
  • Activate Steinberg Audio Power Scheme

See what happens now and let us know?

What we are saying is that if your project structure are in a way that Cubase is running all your plugins on a single core only and will spike the ASIO performance meter, Windows Task Manager will usually just show a lower cpu usage on all cores. This happens because Windows are rotating or shifting the workload between all cores.
So basically you could very well be maxing out your CPU on a single core but cannot see it in task manager.

Did you enable Multi Processing from the Studio–>Studio Setup menu?

So I have now uninstalled Avast anti virus and am seeing about a 10% ASIO performance increase.
I have also enabled steinberg power profile and disabled some smaller helper apps in windows.

I can now lower the driver latency in cubase from maximum latency down to around 6ms without much loss of ASIO performance and have maybe gained about 15% ASIO headroom, so that’s a decent start.

FYI, multi processing and ASIO guard are enabled in Cubase.

Oh, my previous comment didn’t post for some reason.
Before trying to remove Avast, I reverted back to the On board graphics card and disabled the Nvidia card. The result was that the latency of 1ms no longer showed up in LatencyMon, however, there was no benefit to ASIO performance in cubase.

a new project with a couple of VSTis loaded, results in ASIO performance usage of about 3-4% only.

Try the idea that I posted a few posts back about doing a clean install of the Nvidia driver. The clean install removes those unwanted/needed (unless you are a big gamer) programs. Doing that to my Nvidia 960 and (if applicable for you) removing the 2nd Realtek audio driver (the HD one) from the motherboard really helped.

Regards :sunglasses:

Thanks, but wouldn’t completely deactivating the card have a similar effect? There would be nothing loading the nvidia driver in that case.
Regardless though, I have just done a clean install of the nvidia driver and that is how I always install the nvidia drivers anyway. I have already removed the realtek driver tooI. In my case, these didn’t help in a noticeable way.

Even if you deactivated the card the other programs that Nvidia installs would still be loading. But, since you say you do a clean install then… those programs would not be loading because they would not be there.

Sorry… I hoped it would have helped you as much as it cleared my issues. :wink:

I’ll just mention a few other things to consider… make sure the driver for your monitor is up to date. Also, since you said you upgraded your Cubase software… are you running it with a real old USB dongle? I see that some have reported an improvement to Cubase in general with a newer dongle.

Regards :sunglasses:

No, problem - thanks for trying!

I did actually have an old and new dongle side by side and you made me notice that I don’t need to keep the old one in now… I have removed it but am not seeing any improvement in ASIO performance.

I just check the drivers for monitors and there are no new ones available.