Why the Pentium 4 can no longer do simple web browsing?

Question

Back in 2005, my first PC was somewhat underpowered:

• Some ASRock motherboard with S3 Pro Savage onboard graphics
• Celeron 2.0Ghz
• 256+128MiB of RAM
• 10GB HDD

Yet I was still able to do everyday computing with WinXP, Office 2003, and play a plenty of games on it, such as Counter-Strike and Heroes 3. The CPU is even fast enough to play RTS games like Age of Empires and StarCraft. More complex 3D games like Warcraft III is possible after I added a GeForce2 MX400 32MiB. Some Internet cafe even used the terrible Celeron 1.0Ghz, paired with the above mentioned video card, to run 3D games like MU Online very well. Web browsing using Internet Explorer 6-7-8 felt smooth.

And today, I dug up an ancient computer which was once my dream:

• A socket 478 motherboard with chipset 845G
• Pentium 4 2.8Ghz (single core with no model number)
• 512 + 256MiB of RAM
• Maxtor 20GB ATA HDD

With a lightweight Puppy Linux 5.2.8 installed, I found it impossible to do basic web browsing. I've tried a few different browsers, the result is the same: 100% CPU load, 10-15 seconds to load a simple website, sluggish performance, and complex sites like YouTube takes forever to load. I still had a lot of unused RAM.

What has changed in the world of web development that makes simple browsing no longer possible on a Pentium 4?

Answer 1

YouTube uses high compression video codecs such as h.264. These video codec require a lot of CPU power. On modern CPUs instructions have been added to make these kinds of tasks easier and we also have shifted the decoding to the graphics card which has a dedicated part to do video decoding.

On your old system the CPU has to do all the work the hard way and cannot rely on the graphics card either as it would lack the decoder blocks available on newer cards. As a result your system simply isn't powerful enough for modern video.

768MB also is not much by modern standards. Web browsers and web pages are far larger than they were 15 years ago and have a lot more dynamic elements and scripts. That results in a far larger memory and computational footprint. Scripts that didn't exist 15 years ago now take time to execute, and it all adds up.

Modern browser also rely on multiple cores, leveraging the system to decode and execute multiple parts at the same time. Your single core CPU means everything must fight for time on the CPU causing it to become a bottleneck.

Modern CPUs can do a lot more, clock for clock, due to improvements in efficiency and optimisation.

What this means is that your old CPU is slow, and is bottlenecking the page loading.

To put it bluntly, your system is memory starved and lacks the power for the modern world. It might have been fast 15 years ago, but that is a long time ago and the internet was a far different place back then.