How to reinstall a OS for the second time

[putts832]

I need to reinstall W7 OS for the second time using my Curcial 256 SSD. I have heard you don't need to format nor partion the SSD. Just install W7 using the CD. Is that right? If not what is the right was?

 

[rolli59]

If you do not do format then you will end up with two Win 7 installation unless you just do a repair install when it detects the old install. If you do a format do a quick format (low level).

 

[WyomingKnott]

1) Win7 install will offer to repartition/reformat the device. If you let it, then your format was done right there.

2) If you install Win7 to the EXISTING partition, it will overwrite whatever is there. You will only end up with a second install if you specify another partition.

3) Because this is an SSD, it would be a good idea to do a Secure Erase on the drive before the second installation. That way the SSD's firmware will not think that blocks are allocated when they are actually free. This can impact performance in the long run.

 

[putts832]

1) Win7 install will offer to repartition/reformat the device. If you let it, then your format was done right there.

2) If you install Win7 to the EXISTING partition, it will overwrite whatever is there. You will only end up with a second install if you specify another partition.

3) Because this is an SSD, it would be a good idea to do a Secure Erase on the drive before the second installation. That way the SSD's firmware will not think that blocks are allocated when they are actually free. This can impact performance in the long run.

Can I ask you what you mean by a Secure Erase? This is something new to me.

 

[WyomingKnott]

Ahh. The short answer is that it is a command written into the ATA interface several years ago. It instructs the drive to erase itself. I found out about it reading a document from the National Institute of Standards and Technology: http://csrc.nist.gov/publications/nistpubs/800-88/NISTSP800-88_rev1.pdf . It is listed as the best way to erase data on a drive securely.

Longer answer 1: When I want to do a Secure Erase, I boot the Parted Magic utility CD and do it from there. There are lots of other ways, but I haven't found a Windows utility to do it.

Longer answer 2: Why bother? SSDs do funny mapping tricks with blocks. If the OS tells an HDD to store this data at this address, it will. An SSD will remap to some other address, as part of algorithms to use memory efficiently and "wear leveling." The SSD keeps track of which blocks of flash memory are free. If you reformat the drive, you free up those blocks but the SSD does not know this; inefficiency results.

How inefficient the result is, and what can be done to fix it, or whether the SSD will cure itself over time, is the subject of a religious debate and I will not address that.

But the Secure Erase lets the SSD know that all of the blocks are unused, giving you a much better starting point for your install.