Protecting the HD - ensuring longevity

[IWT]

I've bought the brand new iMac 21.5 1TB.

There is conflicting advice about if/when you should put the HD to sleep. By default, 10 minutes. Some books say one hour, two etc and some say keep it on all the time - sleep-restart-sleep-restart "bad" for HD. Some advise manually overnight. Of course during sleep you lose the hourly back ups to Time Machine and there could be background housekeeping which the Mac does over night.

What is the accepted wisdom? What's best for the HD?

Ian

 

[bobtomay]

You're going to get the same responses all over the board here that you have been reading everywhere else.


(Just as a side note: if the HD is asleep, that means you're not using it. Therefore, there have been no changes to the hard drive and there would not be an hourly backup since those only backup any changes made to the drive.)

 

[pigoo3]

Have you ever heard of MTBF?

It stands for Mean Time Between Failures. It's been fairly well written about that hard drive companies exaggerate their MTBF claims...since some of their MTFB numbers would suggest that hard drives should last as long as 57 years before they fail.

But...when you take into account the factors of:

- total spin time
- number of start/stop cycles
- cumulative heat stress
- motion abuse
- statistical quality variation between hard drives

The more realistic life-span of a hard drive is something like 5-7 years. That would be for a hard drive that is pretty much used everyday.

Obviously some hard drives will last longer, some shorter...and if a computer hard drive isn't used everyday (in the case where a user may not use their computer everyday, or may have 2-3 computers)...then a hard drive will last much longer.

As far as your question regarding hard drive sleep time. Start/stop cycles are one factor in the "wearing out" of a hard drive (among other factors)...so if you set your hard drives "sleep" time too short you will have more start/stop cycles.

Personally I think 10 minutes is pretty short...something like 20-30 minutes might be better (just my personal opinion)...but it really depends on what sort of computer tasks you do. If you access your hard drive a lot then a longer "sleep" setting would be better.

But at the "end of the day"...a hard drive will probably last 5-7 years. A replacement hard drive will cost you around $100 dollars or even less. And if you keep your files backed up...there really is no reason to worry about your hard drive.

Just relax...don't stress about the details...and enjoy your computer!

- Nick

 

[IWT]

Thank you both very much indeed. Pigoo3, I've learnt a heck of a lot from you and I am most grateful. Ian