On the way down to Jim Heaney’s wedding, we stopped overnight at my inlaws’ place in Lakewood, NJ. They own one of the four Macs in the family, an 800 MHz G4 iMac (one of the Luxo Jr models). I had bought Leopard as a family pack with the intention of upgrading everyone, but I hit a surprising snag: Apple’s Leopard Installer actually enforces the 867 MHz minimum clock speed cited on the box specs! So for lack of 67 MHz, the disk won’t install.
Fortunately, there are a few workarounds. One is, if you happen to have another Mac handy, to boot the iMac in target disk mode and install the OS that way. The problem is that I don’t have my MacBook Pro with me, and I’m not sure if the iMac even supports booting into target disk mode.
The second, which I’m doing now, is to make a patched copy of the install DVD that disables the speed check. The linked article helpfully explains how to do the patch (and provides an example file) and even provides screenshots to show the process. I am currently making a read-write disk image from the install DVD and once I get a double-layer DVD to burn it to we’ll be able to move forward.
What are the risks? Well, I think the biggest risk is that some of the new Core Animation features will tax the processor and slow things down. So we’ll have to watch that. But being able to remote into my inlaws’ computer and help them will be worth it, as will the putatively improved iChat experience. And a quick check of comments of people who have done this hack suggests that any degradation of performance on an 800 MHz machine will be minimal, so in this case I think the risks are outweighed by the rewards.