Hard Drive Reliability

Hard Drives: What we are learning from data centers.
In a recently published study of Microsoft data centers, it was revealed that 89% of component failures are hard drive failures; in an environment where the hard drives represent less than 30% of the components, I take this to be very significant. The study went on to identify the type of failure and concludes that high relative humidity, not heat is the biggest killer. The humidity being in excess of 60% seems to more than double the rate of failure versus less than 60%. Combine this with a few other reports regarding home computers where smokey environments and environments with airborne small particles (kitchens, manufacturing, etc.) double the failure rate over relatively clean dry environments and a picture begins to emerge. The modern hard drive with a sealed chamber for the spinning disk and read / write heads is fairly safe from environmental impact on the disk surfaces; but, the exposed electronics still suffer from a range of issues depending on the environment. Whether it be corrosion or debris build up, doesn’t seem to matter; failures occur in a wide range of exposures to the circuit boards commonly built on the bottom of the drive.

Now hard drive failure is the one thing we, as users, cannot afford; it means data loss, picture loss, document loss, boot failure, all the bad things. CPU failure, video adapter failure, even motherboard failure are all minor inconveniences by comparison to hard drive failure. So, how long should I expect my hard drive to last? Standard hard drives are very reliable for 3 years; enterprise hard drives for 5 years; Solid State Drives (SSD’s) 6 years. These are not equivalent numbers; The 3 and 5 years for spinning hard drives is just that, they age whether they are being used or not. The 6 years for SSD’s is power on years; they appear to not age when not in use.

Now please take note, the tests that lead me to these conclusions took place in data centers, numbers for home computers might be slightly different. I have a machine with a 10 year old drive that still works but I have seen plenty of dead 2 year old drives too; a lot depends on what kind of life the computer has; good care leads to longer life, cleanliness leads to longer life.