What To Do If The Mac Hangs on Startup

At the end of the day, if your Apple Mac system hangs at startup, it could be anything, but in my experience there are usually a number of steps to take, starting with looking at the hard drive and the RAM, that act as a clear step-by-step process of deducation.

To start off I would setup the Mac in FireWire Disk mode or boot if off an external drive containing a valid system. From there I would use a combination of utilities starting with apple’s own Disk Utility to check the validity of the file system on the internal hard drive, I would also use this to check and repair any permission, assuming that the first test on the file system comes up ok.

The chances are, if your internal hard drive is just plain fried, or their is an issue with the wires and connectors, that when you boot into the external drive, or from CD/DVD and start using Disk Utility that the drive will not even show up in the list of available devices. To check against this kind of fault you need to take the drive out and test it in and external case, either with the same Macintosh system or another.

When you boot of an external drive and continue to experience operational problems I would start to consider looking internally at the RAM. This is always an easy culprit and can usually fix issues by removing any additional RAM that may have been added on top of the pre-installed configuration. If you have multiple chips you will have to test them by adding them one by one to deduce which, if any, are causing issues.

If whilst having removed the RAM, rebooted using an external device or CD/DVD, you continue to experience issues, then there must be some other more serious issue internally with the Macintosh computer, the kind of issue that is beyond most people tampering, and potentially voiding a warranty. If the computer is within its warranty period and or just past the end of it, I would certainly take it to a Mac store and see what they can do.