New computers don't speed up old code

Why HN readers recommended it

Used as evidence that CPU speed for branchy, dependent code has improved only modestly in 15-20 years, so software optimization matters.

This is a summary from the source dataset, not an endorsement by Hacker News or the video creator.

Video & recommendation details

Creator / channel

Matthias random stuff

Topic

cpu performance over time

Format

explainer

Level

intermediate

HN recommenders in dataset

3

HN mentions in dataset

4

Recommendation years in dataset

2025–2025

These counts and years describe the included Hacker News records; they are not YouTube views or the video’s publication date.

From the original HN conversations

Excerpts from the recorded comments. Follow each source for the full comment and surrounding discussion.

• This great video [0] demonstrates how CPU performance has only increased 1.5-2x over the past 15(!) years when executing extremely branchy code. Really shows you just how deep modern CPU pipelines have become. The video also showcases a much more impressive branchless speedup: computing CRC …

• Maybe since 1980. I recently watched a video that can be summarised quite simply as: "Computers today aren't that much faster than the computers of 20 years ago, unless you specifically code for them". [VIDEO] It's a little bit ham-fisted, as the author was shirking …

• Watch this video: [VIDEO] New computers aren't as much faster as benchmarks would lead you to believe. If your code relies on unpredictable branches, dependept memory accesses in a tight loop, or very tight feedback loops inside computations, new CPUs won't have that much of …