KT7AGuy wrote:

... I've read the documentation that came with DiskFresh. It recommends doing the read/write refresh 3 or 4 times per year. This seems excessive to me. clueless1 says that he does the refresh once or twice per year which seems like a much better plan to me. Refreshing a slow USB 2.0 500gb hard drive took almost 16 hours, so this is a very lengthy process to be running quarterly ...

My conservative refreshing recipe for cold storage archival drives (that lay unpowered in a drawer most of the time):

- HDDs: every 6~12 months

- MLC SSDs: every 3~6 months

- 3D TLC SSDs: every 3 months

- Planar TLC SSDs: every month (http://forums.anandtech.com/showpost.php?p=37 … 45&postcount=16)

- USB Flash drives (pen drives): nowadays most budget ones use bottom of the barrel planar TLC NAND == not reliable for any long term storage.

clueless1 wrote:

Another option that I don't think has been mentioned yet is Macrium Reflect. Personal version is free. On my XP time machine I have a 2nd drive that is larger than the 1st and just create images of C: to D: so the backup images are stored on a different physical disk. It's very similar in function to old programs like Norton Ghost or Drive Image. Can be run from and recovered from within the OS or with a Macrium Reflect boot CD (in the event you can't boot into OS).

^ I concur, Macrium Reflect works fine.

I'm trying DiskFresh. I do like that it runs in the booted OS so you can still do stuff. Running it on my 750GB backup drive and it's pretty slow. I'm estimating about 10 hrs and it's on a SATA interface.

Interesting thread about data retention in the Anandtech forum:

Expected life with NAND based devices *unpowered*