Which clock speed metric is applicable in DAWs?

Question

According to this answer, it is not only the number of CPU cores which matters in large DAW projects, but also the clock speed of each core. Alarmingly, the average clock speeds I'm seeing seem to be lower than they were ~10 years ago. For example, my current, 9 year old laptop has a 2.6 GHz i7 CPU, while even many modern i9 CPUs have cores with 1.6 GHz and 2.2 GHz Base Frequency (some other models have even lower). However, there is also a new metric called the Max Turbo Frequency, which in the linked example is a more respectable 4.1 GHz and 5.8 GHz. From the website's resources page...

What Is Max Turbo Frequency? When handling light workloads, the CPU runs at the base frequency listed in its specifications. (Or lower, when the energy-saving Intel SpeedStep® technology scales CPU speeds.) When handling hardware threads marked for high performance, Intel® Turbo Boost Technology increases the clock speed up to the Max Turbo Frequency.

Note that depending on its situation, a given CPU may not always reach its Max Turbo Frequency. The dynamic increase in speed changes depending on the workload and the thermal headroom available.

When comparing CPU clock speeds, the Max Turbo Frequency is typically the key number to keep in mind. It reflects the processor’s peak performance before overclocking. Altering clock frequency or voltage may damage or reduce the useful life of the processor and other system components, and may reduce system stability and performance. Product warranties may not apply if the processor is operated beyond its specifications. Check with the manufacturers of system and components for additional details. Along with core count and premium features, it’s one of the key considerations when CPU shopping.

There is also a Turbo Boost Max Technology 3.0 Frequency and a Thermal Velocity Boost Frequency listed, for the CPU as a whole rather than each core type.

Which clock speed metric would be applicable in a DAW setting? I'm not sure whether the manufacturer's claim that Max Turbo Frequency is typically the key number is correct or just a sales gimmick to focus attention on a bigger number, and I'm not sure if DAWs are special in this regard (in general, I think DAWs are a bit unusual in that they still care about clock speed at all). Should low Base Frequency GHz numbers be a red (/yellow) flag? If it makes a difference, I currently use the DAW Cakewalk by Bandlab.

Answer 1

The most relevant parameter affecting laptop performance is the number of watts of power that the cooling system can remove from the system. So it depends more on the laptop construction than on the CPU itself.

The CPUs mounted in the laptops are very often too strong for the cooling capabilities. This is fine for short tasks, but when running continuously under big load, the performance is throttled, often within less than a minute. When working on music, you normally need to disable powersaving features, which adds to the overall thermal load. Temporary CPU speed boosts may not be so relevant for music production.

The manufacturers don't always provide much details about cooling performance. In such case, you may look for reviews and users benchmark tests. Power of the power supply is a hint. CPU Thermal Design Power (TDP) is another hint. Note, that laptop manufacturers sometimes decrease TDP of a CPU further. Performance characteristics of a CPU mounted in a particular laptop might be lower than those given by the CPU manufacturer, and will vary between various laptop models.

Newer generations of processors may compute faster than the older ones (at the same clock rate), and generate less heat.

Another parameter relevant for real time audio, is the maximum DPC latency. This represent length of occasional CPU interrupts by the operating system. DPC depends on all components of the computer, and also their drivers, thus the whole system, not just the CPU. Again, the numbers can be typically found only in users benchmarks. Luckily, there is a push from gaming community for low DPC, and sometimes new drivers can improve DPC.

Depending on what you do, speed of RAM (and its capacity), and speed of SSDs may be relevant for audio production.

Finally, recording and mixing several tracks using several plugins may not require so much computing power. A lightweight "business" laptop might do the job and be more handy than a heavy and expensive gaming or workstation laptop.

Answer 2

Clock speed hasn't been a meaningful indicator of processing power for many years. Back in the olden days, a microprocessor might do one thing in a clock cycle. These days, processors are pipelined, so they can be loading data for the next instruction before they have finished the current one.

And most computers now have multi-core processors. Go back a few years, and dual core was something special. Now six or more cores is normal.

As for the "turbo boost", manufacturers realised that they could save power by running the clock at a low speed most of the time, and then "overclock" the processor to a much higher speed when needed, but only for a few seconds at a time. They can't keep the speed high for too long as the processor would overheat. The exact nature of the boost is liable to be different for server, desktop and laptop processors. Laptops have the most to gain by using it, as they can only handle a limited amount of heat.