There's been a quiet little movement of new PowerPC software lately, and the headliner is PowerFox — a brand new modern web browser for PowerPC Macs. Originally aimed at OS X 10.5 and PowerMac G5s, it now has a PowerMac G4-capable build and runs on 10.4 Tiger. Unlike previous "modern" PowerPC browsers that were duct tape and dryer lint glued to a Firefox ESR release from 2008, PowerFox is a full-fledged port with dramatically better compatibility. It's made by none other than the talented retro hacker JazzzNY, who long-time viewers (if I have such a thing) will recognize.


I really wanted to put PowerFox through its paces, and a few other new pieces of retro software while I was at it, but my PowerMac G4's PSU kicked the bucket — mid-stream, during development, no less. The PSU was so flakey the computer wouldn't go to sleep and required physically unplugging it after every shut down. Fortunately I'd already bought a replacement that I'd previously tried (and failed) to install. The difference this time is I have a modified GPU in my dual 1.4 GHz G4, the Wind Tunnel. I'm not sure if there's any official bookkeeping on this, but it has to be the loudest Mac Apple ever released. It annoys me to even have it on, but I also really like having a dual G4 — it's my most-used retro machine since it's also my dev box (2 GB of RAM and a SATA SSD).

Resurrecting the Wind Tunnel

If I'm replacing the PSU I figured I'd do something about the noise too, with a pile of fans and a fan controller.

The first time I tried this mod, I had the OEM 9200 Pro installed — the factory GPU. Apple has never been able to do things by the book, and generally that's been to the detriment of their computers. During the AGP era, Apple thought it'd be really cool to invent the Apple Display Connector, ADC for short. Not the worst idea — it shoehorned DVI + USB + power into one cable for Apple Displays — but it only delivered 100W and never adopted DVI-DL, capping it at 1920 x 1200. I swear there was a non-Apple display that used ADC, but I can't find one. I suspected my failed PSU mod last time was due to ADC, so this round I used a 9600 Pro pulled from a G5, modded by disabling pins 3 and 11 and hacking off the hook so it'd fit my G4. (I originally did this to play the very broken PowerPC port of Grand Theft Auto 3, but that's another story.)

The magic that makes the ATX PSU mod possible is a custom harness cable I bought off eBay. Everything else is a sloppy mod, and as my friend Quin said, "These computers were made for shitty mods."

Then it was time to wedge in fans. The Power Mac G4 dates back to the 2-pin fan era, where the computer literally kicks out more voltage to the fan as the CPU temperature gauge climbs. Fans have advanced a lot in the 23 years since this computer was released. My idea was to replace the bulky 120mm case fan with a Noctua. My first attempt used a 2-pin-to-3-pin adapter on Apple's existing fan header. It kinda worked, but it wasn't kicking out enough power to properly cool — the computer crashed at 70°C. I should've known I wasn't going to get away that cheaply, so the second round was a PWM fan controller, an 80mm slim Noctua, and a 60mm Noctua for the upper case. Result: a machine that used to flirt with the high 60s°C now doesn't crack 50°C. I also unplugged the nearly worthless optical bay fan. The biggest source of noise now is the PSU fan, which uses a less-common 15mm-deep fan — that's a project for another day.

It's a novelty now having a Power Mac G4 that properly goes to sleep.

PowerFox vs. AquaFox

For context: the previous "best PowerPC Mac browser" was AquaFox, a fork of TenFourFox, which was itself a fork of the last official Firefox for PowerPC Macs from 2011. The core of AquaFox is 15 years old with new features grafted on. PowerFox is different — it's a fork of Basilisk, which is an independent fork of Firefox that's still being actively developed. To break that into plain speak: Mozilla moved Firefox to the Rust programming language in 2017, and Rust doesn't have compilers for very old systems like PowerPC OS X. Basilisk kept the old C++ codebase going while bolting on modern features, and PowerFox rides on top of that. The guts are much newer than anything else on PowerPC, even if it's still hinging on an esoteric Firefox fork.

Performance is... tolerable. It's less janky than when I used X11 to pipe Firefox from a Raspberry Pi 5, but you're not going to mistake it for a modern machine.

I tried to benchmark this thing and most browser benchmarks straight up failed, likely due to memory and JavaScript requirements. Speedometer 3.1 froze after a few tests. JetStream 3 errored out (it requires WebAssembly, so realistically it was never going to work). Basemark impressively finished and scored a 9 — that's very low, but the fact it can complete the suite at all is remarkable. For reference, my M4 Pro scores 1800.

The more useful but antiquated benchmark for retro browsers is HTML5Test, which maps a browser's capabilities. PowerFox scores 449, AquaFox scores 407 — meaning PowerFox passes more tests and is more likely to render a site correctly. In BrowserAudit (similar in spirit), PowerFox passed nearly every test; AquaFox couldn't even execute the suite. Ironically, PowerFox scored higher in HTML5Test than Helium, a Chromium fork on my modern Mac. Do with that what you will.

Real-world surfing

The modern internet is a bit out of bounds for a computer this old. Just loading a Google search spikes both CPUs to near 100%. uBlock Origin Legacy is almost a requirement to lessen the JavaScript burden. PowerFox is a touch slower than AquaFox, but it can actually load Ars Technica and render it mostly correctly. AquaFox crashed the first time I loaded it and was a mess once it did open — I couldn't click on grid settings, whereas PowerFox handled it.

I was able to load my own blog, but sites like my Hotline Navigator page that lean on WebGL for the background outright don't render — you can still browse the site, you just don't get the eye candy. I did the obligatory watch-my-own-video YouTube test. Amazingly, I got to a video page, but it took two minutes for a video to load and another five before it was actually playing back, slideshow-style. Lowering the quality to 240p didn't help. Don't get me wrong, the fact this works at all is amazing — but you're not going to enjoyably surf the modern web on a PowerMac G4. The web is JavaScript-heavy, and in the era of vibe coding, expect more 5MB PNGs on homepages, leftover testing frameworks shipped to prod, and Claude Code shipping its own source files into the bundle.

The nice thing is PowerFox works well enough to use GitHub, which is huge for retro development.

Other recent PowerPC wins

While I'm here, a few other pieces of new-ish retro software worth checking out:

None of this turns a 23-year-old PowerMac into a daily driver, but the fact that we're getting genuinely new PowerPC software in 2026 — not just maintenance forks of forks of forks — is the most exciting thing to happen in this corner of computing in years. PowerFox alone is a bigger jump in browser capability than anything we've seen on PPC in over a decade.

Go grab it: powerfox.jazzzny.me.