Any way to lighten Audacity's CPU/resources usage for an old PC?

Hi, I’ve been using Audacity in my main computer (2014 powerful PC) to record my electric guitar for a few years, working great, but last month my PC got broken, so I have to use now an old PC of mine (from 2008). It’s a desktop DELL OptiPlex 755, but I improved the heck out of it, so this is my system:

Brand and model: DELL OptiPlex 755
CPU: Intel Core2 Quad Processor Q9550 @2.83 GHz (4 cores, 4 threads), 12 MB L2 Cache, 1333MHz Bus Speed
GPU: nVIDIA GT 730 1GB GDDR3 LowProfile 25W
RAM: 4GB (x4 slots 1GB 800MHz PC2-6400 DDR2-SDRAM UDIMM)
OS: Windows 10 x64 1909 (latest version)
Resolution: SXGA 1280x1024 5:4 ratio
Motherboard: DELL DR845
Chipset: Intel Q35 (Bearlake-Q) + ICH9DO
Audio adapter: Intel 82801IB ICH9

I’m using, to record the guitar, an external interface (Zoom G3X) via USB. The guitar gets plugged into the G3X, the G3X goes to the PC via USB, and that’s it. I installed the official ASIO driver for my G3X, like in my (now) broken PC, and it’s recognized just like always in Audacity. The problem is, when I record the guitar, the sound recorded gets all popping and crackling. I normally record while listening to backing tracks I added to the project. If I have like 5 tracks added and record the guitar, it gets much more clicky and poppy than if I record the guitar without any other tracks added to the project.

I’ve tried different USB ports, nothing, setting the buffer from 100 ms to 1000 ms, but still, it clicks. If I use extensively the CPU meanwhile (checking purposes), the clicks start to appear a lot more. This is not only happening while recording. If I play back the recorded track, or any track, in Audacity, and play it back while using the CPU extensively, the same clicks appear. If I am playing back, say, 5 tracks and try to record the guitar (listen to the backing tracks while recording), the clicks appear much often, although not as much as when I squeeze the CPU.

So, everything seems to point that the CPU can’t handle… audio recording?
I know it’s a 2008 Intel CPU, but still, it was almost the best one out there when it came out. This Zoom unit was released in 2011, so by then, a Q9550 was like having an Intel Core i5-760 @2.80GHz (checked performance, roughly the same). That was a nice CPU at the time, and I doubt you needed anything like that to simply record yourself.

I don’t know where the workload relies when recording my electric guitar into Audacity… the Zoom G3X can’t be because then it should work like before, the GPU can’t be, RAM neither because it’s 40% free all the time, may be the CPU or the sound card?

Anyways, besides pointing out what can be wrong with my rig, I’d like to know if there’s something I can do to soften the CPU use, overall usage of resources. May be like disabling the real time waveform created by Audacity while recording?

I don’t know, whatever helps Audacity to run with minimal CPU usage, without compromising sound quality (such us going 8000 Hz or something like that). I provide an example of the recorded guitar with clicks down here. I also put here the results of an audio scan tool that detects errors:

Probably the best performance boost could be achieved by changing the operating system to a light-weight Linux distribution.
I use Xubuntu, which is full featured and pretty light. There are even lighter versions of Linux available, though the lightest ones do cut down on a few features.

If you want to stick with Windows 10, then disabling animations can save a lot of resources.

Audacity itself is pretty light on resources, so there’s not much room for improvement to be made with Audacity settings.
You may find some improvement by not running Audacity full screen (this can be very noticeable on Mac computers with Retina displays - I’m guessing that it is likely to also have some affect on Windows).

Thanks Steve. But, what can I do to check what component is the one struggling? Could it be just drivers?
Can’t the Q9550 keep up with the recording?
Seems pretty, pretty weird, we are not talking about a 2005 laptop.
Must stick with W10. Aren’t there options to lighten some workload?
Like not creating a real time waveform of the recording sound.

It’s not just drop-outs there is a fade-in immediately after …

So it looks like other software is interrupting: fighting for control of the audio.

I’d try all permutations of these two tick-boxes on the recording device properties …

The waveform can’t be disabled.

4GB is not a lot of RAM for 64-bit Windows 10. It’s pretty close to the usable minimum.

Audacity is shipped without ASIO support (due to licensing), so it cannot use ASIO drivers. If ASIO is running, you are very likely to get sound problems because ASIO will be trying to keep exclusive access to the audio device. This “could” be the main cause of your sound problems.

Wow, thank you very much for the detailed replies. OK, the waveform can’t be disabled.

It’s really interesting that you analyzed the wave. I will definitely try those ticks and see if they affect.

I was using this same rig with my broken PC and worked just fine. May be I should uninstall the ASIO drivers and try other way to get the sound? How?

May be in my broken PC I didn’t install the ASIO driver, I don’t remember.

NOTHING, tried those boxes, no luck.

How about increasing Audacity’s CPU priority to “above normal” to give it the upper hand.

I’ll try and post results.

OK, so after a lot of searching, I sadly tried an alternative of Audacity, and just in case, with built in ASIO support. I tried Reaper software. Magically, Reaper does not click when recording, it records finally my guitar as Audacity did in my last PC. I’m asking myself now how is it that I could totally record using the G3X. I’m starting to think I did not installed any ASIO drivers, and that the G3X was recognized “just because”?

I’d love to know what is doing what. My electric guitar sends analog signal, my G3X converts it to digital, sends that via USB, then what?
Is it the CPU that interprets in real time that stream of data? What in heaven a sound card is for then?

I never understood what sound cards are for anyways, why someone would buy a $90 PCI-e instead of using the built in MoBo.