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Comment by cmeacham98 | Hacker News Reader

The literal clock speed of CPUs has been stalling, but CPU performance is and has been on a massive increasing trend effectively ever since AMD released the first Ryzen CPUs.

Recent product announcements from Intel and AMD show no sign of slowing down. Sure it's not the 'double performance in 1-2 generations' of the olden days, but it's definitely not stalled either.

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The improvements outside the processor matter more for a typical user. DDR5, PCIe5, USB4, Bluetooth 5.2, WiFi 6E, etc. These recent version bumps make everything feel faster, but the CPU gains are indeed coming much slower and at vastly higher cost. Die shrinks will likely reach their physical limit this decade for traditional silicon.

The Ryzen 7 2700X chip I bought back in 2018 is still fairly close to the latest Ryzen 9 chips in terms of single-core performance on benchmarks (within 10% IIRC). The Ryzen 7 is an 8-core (16 thread) CPU, and now you can get 12 or 16 core Ryzen 9's, but most workloads don't take proper advantage of even an 8-core machine.

Quick online research shows a 30%-40% single core improvement from the 2700X to the 5700X, and a 40% to 50% (single core) improvement to the 5900X. Maybe you have a specific weird workload that isn't improved much, but performance improvement for the average workload is much better than 10%.

This is only in benchmarks.

Most workloads don't even take proper advantage of more than 1 core. Single core performance is still the most important metric and there hasn't been anything exciting regarding that in the last... 15 years?

This is true. However your workload runs in a multitasking OS which, at least for Win 10, needs at least a core only for itself.

One of the reasons why CPUs are getting faster is because the more transistors you have, the faster is the chip and vice versa (this is not a proven statement but rather my intuition). We might not be able to use higher clock frequency, but we still can fit more transistors on the same area.

What’s even more, is we can make higher frequency chips, it just turned out higher density gates was the easier path to go down.

If the gates path reaches its end, we can still go back to clock. It won’t be easy or cheap to solve all the clock problems, but if it’s better than the alternative someone will do it (like how fracking only became viable as a means of drilling oil once the cheap, easy to get oil was somewhat depleted)

By the way, why did clock frequency stop around 3-4 GHz? I assume that as transistors become smaller, their propagation delay decreases, as their power consumption, and it allows to use higher clock frequencies. Is there something else that I am missing?

Propagation delay doesn't decrease from one end of the chip to the other if you keep the same area in total.

Power consumption and the resulting heat.

The top-of-the-line next generation of chips will be solidly clocked at 5GHz and above.

https://hothardware.com/news/amd-computex-taipei-2022-keynot...

I believe mainframes have had CPUs operating around this for a while as well.

Even account for security vuln mitigations? As an aside, is there a good table somewhere listing all of the Meltdown/Spectre etc. vulns and current status regarding software and hardware fixes? My understanding is most still don't have hardware fixes yet.

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