thevisi0nary wrote:Another thing I've noticed is the difference in how gaming performance and low latency audio performance differ. Gaming seems to benefit from clocks, even with the lower ipc on intel, while audio performance does not seem to care about clock speed as much.
If you consider the amount of data being shunted through the CPU by digital audio it's pretty low bandwidth compared to the vast amount of number crunching required for generating 3D scenes to render at decent framerates, even if the GPU is taking up much of the geometry calculations and rendering load.
In gaming a 3D scene has to be defined, a processing pipeline kept fed and framerate is paramount. Clock speed counts because the CPU is doing a lot of work: updating the scene every frame, keeping track of data structures representing graphical objects, handling gaming logic, I/O, networking, audio and so on, even though it's offloading much of the rendering to the GPU (which it has to, due to the phenomenal amount of matrix multiplications and other mathematics involved in rendering a scene).
Pure audio recording and playback is therefore lightweight and was even possible (albeit at lower sample rates and resolution) by the 32-bit 68030 running at 16Mhz on the Atari Falcon back in the day.
Of course modern resolutions and sample rates are higher but not so much that they bother any processor these days. Rather it's the overhead associated with plugins and the DAW itself that up the system requirements.
What audio performance does require more of is low latency, and this is more a function of the interface drivers and system design than it is of the CPU itself. After all, the CPU is effectively sitting there waiting for things to do, doing them, and pushing the result back out again. The surrounding systems responsible for receiving the incoming data stream from the AI driver, delivering it to the CPU in the shortest possible time and then pushing the results back out to the audio interface again have far more effect on the user experience than than CPU itself.
Thus for digital audio a slow CPU within a system that can shunt data to between the AI and the CPU quickly is preferable to a faster CPU in a system with less ingress/egress performance because in the latter case the CPU simply spends more time waiting for that data to arrive and the results take longer to reach the outside world again.
The CPU can only work with the data it is being fed and the means of delivery is outside of its control for the most part. With graphics, the bandwidth between the CPU and the GPU is high and it's local, thus the chip is working hard for much more of the time as opposed to waiting for stuff to come into it to process.
Pete can certainly talk more in detail about this than I can but that's the gist.