Never think that a stored shelf harddrive is ever going to guarantee the next spin-up. Very very dicey johnmeyer.I don't think the likelihood that it will fail to spin up is any different for a drive on a shelf than a drive in your computer when that drive comes out of spin-down, or when the computer is turned on.

The fear of drives failing when they spin up is WAY overblown. If this were really a major problem, pretty much nothing using a disk drive would work: DVRs spin down the drive as soon as no one has been watching TV for a few hours (on my Cicsco DRV, it takes five hours); the disk drive in an disk-based iPod spins up and down all the time; every laptop drive spins down to save power, and then spins back up again; etc.

So, not putting a drive on a shelf is not dicey in any way. I know that some people are concerned about handling a "bare" drive, but that too is overblown, and if you are concerned, just get a system which uses a caddy.

The mythology of drives spinning up/down causes a huge number of people to never turn off their computers. I am not a "save the planet" kind of guy, but I abhor useless waste, and am horrified at the pointless burning of fossil fuel to keep computers running when they aren't doing anything useful. It is an almost criminal waste of resources and is totally unnecessary. It is amazing to me when I meet someone who will carry on all day about driving his Prius, but who leaves his computer running 24/7.

I turn off all my computers every day. Guess what? They do NOT fail when I turn them on.

johnmeyer, while I respect your anecdotal experience, when you have been overseeing corporate IT networks as I have for many years with a thousand workstations deployed... Let me state unequivocally that most drive failures occur from a cold state (shelf or in computer tray) when the drive spins up. Now you could argue that wear and tear contributed, and undoubtedly your right about that, but it is the spin-up that is the true margin of safety measure. This also goes for optical drives, whether they are in a computer tray or in a set-top player.

But there is a big difference in failure between the two drive types because of the nature of what they do with spinning disks and how they control spin. Harddrive is sudden death, optical drive loses momentum or jerks in the speed regulation.

Not doubting your experience, but the only mechanical failure of an HDD I've ever had was a 2 month old HP laptop. (very recent too) I've ALWAYS turned off/on whenever I've stopped - even if I'm just going for a cuppa. I've thrown away/destroyed my HDD's as they've become redundant in size. That goes back well over 20 years. Do any of the HDD manufacturers recommend leaving your computer on 24/7 "in case the disc fails"?

Most light bulb failures happen when you turn on the light. Does this mean I should never turn off the lights in my house or office?

Any light -- or disk drive -- that fails when it is turned on was almost certainly going to fail pretty soon anyway, and therefore blaming it on the slight stress of spinning up, while technically accurate, is also wrong and misleading.

The analogies are endless: most tire blowouts I've had only happen when I'm driving at highway speeds, but of course I do that all the time, and 99.999% of the time, the tires don't blow out. It doesn't stop me from driving at that speed because if the tire isn't worn or defective, driving at highway speed is not a problem.

The same is true of a disk drive: if it is not about to fail anyway, spinning it up is not going to be a problem

But don't take my word for it, listen instead to Google who has more drive experience than the rest of the planet combined. Here's a paragraph from one of the Google Drive Studies:"Power Cycles. The power cycles indicator counts the number of times a drive is powered up and down. In a server-class deployment, in which drives are powered continuously, we do not expect to reach high enough power cycle counts to see any effects on failure rates. Our results find that for drives aged up to two years, this is true, there is no significant correlation between failures and high power cycles count. But for drives 3 years and older, higher power cycle counts can increase the absolute failure rate by over 2%. We believe this is due more to our population mix than to aging effects. Moreover, this correlation could be the effect (not the cause) of troubled machines that require many repair iterations and thus many power cycles to be fixed." **

So, based on actual measurement -- and not anecdotal evidence -- even for older drives, the increase in failure rate is extraordinarily small, and may be due to other factors.


** "Failure Trends in a Large Disk Drive Population", Eduardo Pinheiro, Wolf-Dietrich Weber and Luiz André Barroso -- Google Inc.

Well, so far, Western Digital gets a nod on my original solicitation.

I got a new Dell M3800 laptop and after I had it realized that it had an empty mSATA slot. I didn't know there was such a thing. A little checking around found me a Samsung 1TB SSD drive for around $430. It should be here Saturday. This is in addition to the 1TB WD SSD Hybrid drive that I already had installed.

This will give me a rather light and thin touchscreen laptop with 16GB of RAM, a 2GB nVidia card, a quadcore i7, and a terrabyte each of regular and SSD memory! Gotta love those Black Friday/Cyber Monday deals! Slightly bigger than a Microsoft Surface, but not all that much.