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SamIchi

macrumors 68030
Original poster
Aug 1, 2004
2,716
137
Is the 7 pass really necessary?

Zero out good enough?
 
It depends on how much you need to keep prying eyes away .... :)

I did a 7 pass erase on a 500 Gb disk yesterday, it took 9 hours but I feel happier now putting it on eBay.
 
it depends on what was on the drive and where it's going.

If you only have data that's of minimal threat to you if released into the wild and you're giving the drive to your nephew, zero out is more than enough.

If you're selling a drive that used to contain highly sensitive data and it's going to an eBay purchaser in Nigeria, I'd probably opt for 7-pass.

As an aside: When I worked in the defense contracting environment, I learned that marketing claims about multiple zero out passes meeting DoD government standards were largely baseless: every secret project I worked on required that when the project was over, the drives be pulled from our macs and destroyed under the eyes of a government auditor. The macs were then sold without drives in them.
 
I plan on selling it so I guess I'll go with the 7-pass....

Which brings me to another question. Does it matter how it's connected when erasing?

Initially I had it hooked up via USB, that went through a USB hub.

I just hooked it up directly to the MB via FIrewire.

Since it's not writing any data does the connection even matter?
 
I plan on selling it so I guess I'll go with the 7-pass....

Which brings me to another question. Does it matter how it's connected when erasing?

Initially I had it hooked up via USB, that went through a USB hub.

I just hooked it up directly to the MB via FIrewire.

Since it's not writing any data does the connection even matter?

Of course it's writing data...0s (Zeros) to every sector. Single pass does this once, 7 pass does this 7 times. The larger the disk, the longer it takes.
 
Of course it's writing data...0s (Zeros) to every sector. Single pass does this once, 7 pass does this 7 times. The larger the disk, the longer it takes.

Ahh yes.. sorry.
 
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