According to applehacks.net the procedure is as follows: About step 5: my MacBook Pro 5,5 can't boot Tiger, since the earliest it shipped with is Leopard so I wouldn't be able to boot the ATV's drive, however, I'm wondering if step 8 is really necessary. I have the install disks for an iMac Core Duo which are 10.4.11,beyond 10.4.8 which they claim you need to update to. Hopefully that would mean that the ATV would boot in to the set up process when the rest of the steps are carried out? And yeah, I know there are images for 10.5, but I'd prefer 10.4 as it should be faster and everything I need is supported under 10.4 (also it was the first version of OS X I ever used - on a dell no less - so I have a soft spot for it ). Could anyone who has performed the procedure share some words of wisdom?