How to take care of hard drives?

* Don't bump desktop mechanical drives when they are spinning (probably a good idea to not bump notebook drives either, but they seem to be more tolerant).
* Limit the power cycles as much as you possibly can without making it an inconvenience to yourself.
 
Repartitioning and reformatting drives shouldn't cause failure, but this will depend greatly on the amount of read/write and quality of the unit. I have older drives that have been reformatted plenty of times and they still work. I've also had year old drives die which had only been formatted once so I can't really pull any concrete analysis from that.

When physically moving drives around just take extra care to not strike them on anything obviously, but most drives aren't 3.5" drives aren't going to fail if they simply bump something. The smaller 2.5" laptop drives are a little more fragile so you would try to avoid all physical contact with other objects. More importantly, keep ALL hard drives away from magnetic fields and anything that may emit microwaves or other radiation. Store them in cool dry locations if possible. I also have the tendency to keep my drives on anti-static materials, and spots where they can't accumulate dust.

As for power cycles I haven't seen any proof that this directly affects a drive's life, but that doesn't mean its not true. Normally, I don't leave my machines on when I'm away from home for extended periods of time, and I've never had a drive fail to power on or anything. Again, this may depend on the brand or model but I've never had issues that I could tie to power cycles. They are designed to be powered on and off regularly; go into standby etc.
 
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