If you have Lion, go to the Apple menu -> About this Mac. Then click on the "More Info…" button. The model year should be listed under the model, on the right.

If you have Lion, go to the Apple menu -> About this Mac. Then click on the "More Info…" button. The model year should be listed under the model, on the right. If you don't have Lion, I think you can still get that info from the window that comes up when you click "More Info…", but I forget where (and don't have a machine running Snow Leopard handy ATM). EDIT: The required models are listed by Apple (linked in the article): http://www.apple.com/osx/how-to-upgrade/ http://www.apple.com/osx/how-to-upgrade/