How would i COMPLETELY re-format my Mac Hard drive?

If you just want to erase the data not overwritten during reformatting, click the "Erase Free Space..." button & choose your preferred option for that. Note that this is a volume level step, so you must choose the volume name (not the drive's name/model/capacity item) in Disk Utility's disk list. If for some reason you have partitioned the drive into more than one volume, choose this for each of them.

Alternately, choose the drive's name/model/capacity item from the list & click the "Security Options..." button, again choosing your preferred option for that. This will overwrite everything except the basic partition scheme info, which is generic enough that it contains no personal or sensitive info.

Note that drives are listed without indentation; their volumes are indented under them in the list. All volumes are shown so if you have an external drive attached, make sure you choose the correct volume or drive as the target of the erase. I'm not familiar with what a "232.9GB (random serial) Q Media" drive would be, but it seems unlikely that it would be the internal drive in your iMac, unless you replaced the OEM drive with something else.

As for which erase option to choose for good security, the "Zero Out Data" (one pass) option is probably good enough for all practical purposes, at least on a 200+ GB drive. In theory, the 7 or 35 pass erase is more secure, but according to some sources that only really applies to older, lower density drives that don't use "embedded servo" technology to precisely position the head(s). Also note that the DoD standard referenced in the Apple documentation is not a current one, so if your drive contains anything the military or government considers sensitive, you should contact the appropriate agency for approved erase/disposal methods (usually degaussing or physical destruction).

Do a re-install and select any one out of zero-out data, 7-pass erase or 35-pass erase. Zero-out is the fastest. The other two will take much longer. If you have a large hard drive, this can take a very long time. Zero-out is sufficient.

That will format your drive and you can re-install your OS the way it was when you first got it.

Helooooo wrote:
so this is what i think you are trying to explain to me:

Delete my drive (not Macintosh volume) using Zero out and reinstall my leopard??

Yes, that will work just fine, although your terminology is wrong -- you can't "delete" a drive, only apply a secure erase to some or all of it. You do this using Disk Utility, an application best run for this purpose from the installer disk as follows:

1. Start up from the Leopard installer disk.

2. After you see the language selection screen & make your choice but before you start the install, go to the "Utilities" menu at the top of the screen & select "Disk Utility" from it.

3. Choose the drive from the list. Look carefully at the list & note that some items are indented a few spaces to the right under other items, like in an outline formatted list with headings & subheadings. The indented items are volumes, the non-indented ones are drives. Take care to choose the drive that you want to erase if there is more than one shown. (The installer disk will be shown, too, but it can't be erased.)

4. Select the "Erase" tab in Disk Utility. Verify that the drive is still selected & not some volume under it.

5. Using the "Security Options..." button, choose the "Zero Out data" option, then click the "OK" button. This rolls up the options list & returns you to the main "Erase" window.

6. Verify that the "Volume format" popup list is set to "Mac OS X Extended (Journaled)"

7. If you wish, give the volume a name other than the default "Untitled" one.

8. There is no need to check the "Install OS 9 drivers" option unless this drive will be used with a system capable of starting up directly into OS 9. (It is unlikely that it will.)

9. Click the "Erase" button.

10. Wait ... the process will take quite a while to complete.

11. When it is finished, quit Disk Utility, which takes you back to the OS X Leopard installer.

12. Install OS X normally, following the screen prompts to select the volume you just erased & (optionally) named.

Message was edited by: R C-R

The steps I outlined will delete all preexisting data -- there is no need to run anything beforehand if you follow them exactly. (Erase free space just erases what currently isn't in use, but if you are going to erase the entire disk anyway, it is a superfluous step.)

However, there is no way to end up with a totally blank drive using any Apple software tool, since all require at least a partition scheme to know where to find what it can erase. But as we have explained repeatedly, no user data will remain on the drive, not even the name of any previously created volume, if you follow the instructions to securely erase the drive.

What you will end up with is a drive ready to have OS X installed, with no wasted space or any recoverable trace of the old data it contained. From following several of your topics, this seems to do everything you want, & it does it as simply & efficiently as possible.

The First Aid steps were mentioned to do two things:

• Clear up any confusion about how many & drives & volumes you have attached to your Mac

• Perform a generalized troubleshooting step to specifically address the less-free-space-after-installing-the-OS issue you reported in that thread.

IOW, follow the steps in this thread if you want to start from scratch with an empty as possible hard drive. If you want to address just the less free space issue with whatever is currently installed on the drive, do the First Aid steps instead, as step one of what might require further info or procedures.