10 steps to take when your Mac won't start up (MacWorld UK) -- hope one works for me. [View all]

http://www.macworld.co.uk/news/mac/steps-take-when-your-mac-wont-start-3423817/

This is particularly handy to have if you bought a used Mac and don't have the installer disks for the current system. It's written for 10.8, but some of the tricks go back to the earliest OS X release. I'm going to be trying these out for 10.7, see if I can get my Mac Pro to find the SATA drive again. It can boot from the internal (ATAPI) or USB CD/DVD drive but not from the internal HD I've been using since I bought it -- or from a clone I just made of that drive. Unfortunately, the only bootable CD I can find is Lubuntu -- the Mac Pro 2,1 supposedly can run 10.4 to 10.7, but I can't get it to boot from a 10.6.3 installer disk -- and Lubuntu can't see any SATA disk, only the two CD/DVD drives. I hope it's not the whole SATA bus that's gone bad.