[SOLVED] wiping hdd clean before or after new build?

Solution
Delete the old partition when able to in installer setup, just prior to pointing WIndows where to install to,,,

It will do a quick format automatically. No further elaborate scheme or procedure is necessary.
I would do so beforehand.

Knowing that the drive is wiped clean, reformatted, and hopefully functional would be one less potential source of problems.

And I would also run the applicable drive manufacturer's diagnostic software on the drive to ensure that the drive is functional and healthy.

However, as always, be sure that there is no important data on that drive before you wipe it.

Verify that any data backups from that drive are indeed recoverable and readable.
 
I would do so beforehand.

Knowing that the drive is wiped clean, reformatted, and hopefully functional would be one less potential source of problems.

And I would also run the applicable drive manufacturer's diagnostic software on the drive to ensure that the drive is functional and healthy.

However, as always, be sure that there is no important data on that drive before you wipe it.

Verify that any data backups from that drive are indeed recoverable and readable.
I have backed up everything i wanted from this hdd so should be fine to wipe. Is the dignostic software on the manufacturers website? Its a toshiba data dt01aca 1tn