Processor clock speeds are not how fast AIs think

I often encounter some confusion about whether the fact that synapses in the brain typically fire at frequencies of 1-100 Hz while the clock frequency of a state-of-the-art GPU is on the order of 1 GHz means that AIs think "many orders of magnitude faster" than humans. In this short post, I'll argue that this way of thinking about "cognitive speed" is quite misleading.

The clock speed of a GPU is indeed meaningful: there is a clock inside the GPU that provides some signal that's periodic at a frequency of ~ 1 GHz. However, the corresponding period of ~ 1 nanosecond does not correspond to the timescale of any useful computations done by the GPU. For instance; in the A100 any read/write access into the L1 cache happens every ~ 30 clock cycles and this number goes up to 200-350 clock cycles for the L2 cache. The result [...]

The original text contained 1 footnote which was omitted from this narration.

---

First published:
January 29th, 2024

Source:
https://www.lesswrong.com/posts/adadYCPFAhNqDA5Ye/processor-clock-speeds-are-not-how-fast-ais-think

---

Narrated by TYPE III AUDIO.