ATP is a great show that I started listening to last summer. Every now and then Casey and Marco let John talk about video games, which is more than I can say for letting him do research. On last week’s episode, the post-show discussion was about the PS5’s variable frequency and the Tempest audio engine.
I found it rather interesting to hear folks with way more knowledge on how computers work discuss the probable logic behind Sony’s design decisions for the PS5.
As John pointed out though, we are missing one component of the equation: We have no idea how the PS5 cools itself. Mark Cerny briefly hints at it in an interview with Eurogamer.
“As for the details of the cooling solution, we’re saving them for our teardown, I think you’ll be quite happy with what the engineering team came up with.”
Basically (as far as I understand it), the PS5 has a set power budget for the CPU and GPU, which leads to the variable frequencies instead of a locked frequency that has varying power demands. More from Mark Cerny,
“We don’t use the actual temperature of the die, as that would cause two types of variance between PS5s. One is variance caused by differences in ambient temperature; the console could be in a hotter or cooler location in the room. The other is variance caused by the individual custom chip in the console, some chips run hotter and some chips run cooler. So instead of using the temperature of the die, we use an algorithm in which the frequency depends on CPU and GPU activity information. That keeps behaviour between PS5s consistent.”
Sounds smart to me. This way, every PS5 is ( i.e. should be) identical in performance, giving developers a clearly established threshold.
“The [behavior]* of all PS5s is the same. If you play the same game and go to the same location in the game, it doesn’t matter which custom chip you have and what its transistors are like. It doesn’t matter if you put it in your stereo cabinet or your refrigerator, your PS5 will get the same frequencies for CPU and GPU as any other PS5.”
Marco also shared what he thought of the Tempest audio engine, based off John’s description. Marco has his own audio engine he uses in his app Overcast. It is my podcast player of choice. Marco seems to know a ton about audio, so his insight having not even watched the presentation was interesting.
It was a fun discussion to listen to on ATP and I encourage you to check it out. The link at the top takes you right to when the discussion starts, although the whole episode is great.
*Eurogamer spelled behavior with a “u.” I changed it to the American English way of spelling it.