Trip Report: Snow Leopard PPC

This week, I spent a few minutes burning an old Snow Leopard Developer’s Build to an extra USB Hard Drive.

It worked. My G5 booted up, and I was able to imagine for a bit what Snow Leopard might have been like if it had kept support even for Power Mac G5s. Overall, the system ran okay, keeping in mind that I booted it from an external USB Drive which is a slow way to go about things.

My graphics card, a GeForce 7800 GT, ran just great, even if there were some graphical glitches at work.

But here’s the rub – the mach_kernel used in the build was compiled in October of 2008. The final version of Leopard, 10.5.8, was released August 5, 2009 (per Wikipedia). Snow Leopard came pretty quickly after on August 28, 2009. And while Snow Leopard’s initial release still had a lot of PowerPC code baked in, I’m unaware of anyone getting that code to work on a PowerPC.

During my test, I ended up pulling the kernel and other frameworks from a Snow Leopard install DVD to make a modified Snow Leopard PPC drive. The G5, each time, would start to load but hang. No doubt, the issue is deeper than just getting Snow Leopard to recognize hardware – there are components that do not contain PPC code. Ultimately, it may just not be possible.

One glaring example – my G5 has 10GB of RAM but only 6GB shows up in the Developer’s Build of Snow Leopard. Weird, right?

I will continue to take a look at this, but my hope dimmed a bit today. Leopard 10.5.8 is more recent a release than these Snow Leopard builds. I think it’s always worth tinkering around, but I don’t believe this will open the door to any Snow Leopard-era software. Your mileage may vary, of course, so go follow along on the MacRumors thread.

Update: I queued this post up a couple of days ago, and in that time, we continue to tinker and work with the Snow Leopard development build. I admit I sound a little pessimistic in this post. Some of that is warranted, but other posters are much more positive about what we can achieve. Stay tuned for more updates.

— Nathan

Snow Leopard on PPC

Screenshot from Lars Von Hier at MacRumors

The incredible PowerPC community is at work again, conjuring up some interesting experiments to see how else our machines can be extended.

The biggest nugget that has been circulating is the discovery of early builds of Snow Leopard which included PowerPC compatibility. These images come before Apple decided to nix PowerPC code. As such, they aren’t finished builds of Snow Leopard, and the support for some hardware is sketchy. However, initial reports of those who are trying them out note that Snow Leopard runs fairly well, though graphics drivers are buggy.

I haven’t taken the plunge yet, but I am working up to it as I watch the community learn about these finds and troubleshoot how to get the system stable. For example, kexts and drivers from Leopard (10.5.8) could being copied over when missing in Snow Leopard. Other imaginative thoughts include exploring later Snow Leopard builds for PowerPC code that lingered and moving those pieces back into these pre-release disc images. A Frankenstein kind of experience.

Read the thread on MacRumors to get started: Snow Leopard on Unsupported PPC Machines

Questions that remain:

  • Will this open PPC machines to some later builds of certain software? Would this potentially make some TenFourFox builds easier?
  • Is this stable enough to be a daily driver, and is it truly snappy?
  • What will be incompatible?

— Nathan