[mrssmith]

I just attempted a clean install from Leopard to Snow Leopard. I used the disc utility to erase my HD1, however I chose the default erase option 'Don't erase data' instead of the 'Zero out data'.

Did I still do a 'clean install'? and Is there any difference in terms of performance by not choosing 'Zero out data'?

[macnuke]

zero out..... takes long long time.. writes over the whole hard drive.

default erase..... leaves all the stuff on the drive.... but wipes the directory.

edit....

performance wise..... zero difference.

if you wiped the directory and ran install.... yes, it's considered a clean install....

right up until you use migration assistant or anything maintaining your preferences such as importing everything from a TM backup.

true clean is you install everything from the originals.
my honest opinion is that it's rarely ever needed and is more work than it's worth unless you have screwed up your system beyond any hope of repair.

Diskwarrior and a bootable repair drive is all you should ever need to keep things in order.
a backup is just that, only needed in one of two events....
event one.... total mechanical hard drive failure.
event two.... you screwed up and trashed stuff you didn't mean to.

This post has been edited by macnuke: 29 July 2012 - 07:01 PM