I'm have successfully installed Leopard on my Mac Mini, with a processor speed of 1.66 GHz. I have had no issues whatsoever with Leopard on this machine; I did have the BSOD (Blue Screen Of Death) after Installation, but I easily got rid of that with the fix form Apple.
However, I went through a nightmare when I tried to Install Leopard on my MacBookPro. I put in the disk, and it started up perfectly. Then the install got stuck and 58 minutes remaining. It sat like that for an hour, and I was forced to manually eject the disk. At this point the machine froze, and I rebooted it. I started up as if it was running Leopard; the login window was sitting in front of the Space wallpaper instead of the Blue Wallpaper. However, both my account has disappeared. I tried everything from starting up in Target mode with the other Mac to taking the thing apart. Nothing worked. I ended up sending it to Apple, racking up a bill of $509.
See my thread on it.
- John