Are SSDs or Spinning Hard Drives More Reliable?

Cloud backup company Backblaze publishes a definitive 5-year study

We all use computers for making music, right?

Well, the old wives’ tale about solid state drives being less reliable than traditional spinning hard drives… oops, I just spilled half the beans. Bottom line: consider replacing your spinning drives after four years.

That doesn’t mean you should throw them away, because they’re still useful as backups of what’s on them. But it seems like a very good idea to copy the data off them onto new drives.

That’s my first takeaway after reading an interesting study from cloud data backup company Backblaze. They run big honking servers with hundreds of drives in constant use, and they tracked their failure rate over five years – as definitive and authoritative a study as we’re ever going to see.

What Backblaze found is that spinning drives’ failure rate goes up markedly after five years to about 3.5%, and keeps climbing up to a predicted 7% rate by year eight. Their SSD failure rate started below 1% and stayed pretty much constant, even ticking down a little.

It’s true that SSDs fail all at once, while spinning drives often start acting funky long before they totally crap out. But that’s a reason to back everything up religiously, certainly not to avoid using SSDs.

The only argument for spinning drives is that they’re still somewhat less expensive. At lower capacities that becomes less significant, i.e. we’re talking about smaller amounts of money.

For example, a 1TB 7500 RPM internal spinning drive – a standard hard drive – might run $50, while a 4TB one could be $150. Compare that to maybe $75 for a 1TB SATA III SSD and $350 (probably more) for a 4TB one – and those aren’t the highest-performance SSDs available.

SSDs were a major upgrade when they first appeared, because they’re *so* much faster. However, early on you had to worry a little about the number of read and write cycles they were good for.

At this point the technology has advanced way past that, and the prices are much lower.

And I for one am unlikely to buy any more spinning drives. Does your mileage really vary?