Before you buy a hard drive, you might want to take a look at this:

The Most (and Least) Reliable Hard Drive Brands

Backblaze uses 25,000 hard drives for its online backup service. This has provided some interesting information, such as how long hard drives are likely to last and the difference in reliability between enterprise and consumer drives. Today, Backblaze has spilled the beans on which drive manufacturers are the most reliable.

How Long Your Hard Drive Is Likely to Last

The comparison is between Seagate, Hitachi, and Western Digital. (The company has a few Toshiba and Samsung drives, but not enough for analysis.) Backblaze says they buy the least expensive drives that perform well, based on stress tests and a few weeks in production. P

As with the previous analyses, Backblaze measured the reliability of the drives by looking at the annual failure rate, the average number of failures while running a drive for one year. Here is a pretty telling chart:P

The company has also broken it down by drive model on their blog. The Hitachi GST Deskstar (7K2000, 5K3000, and 7K3000) had the lowest annual failure rates, from 0.9% to 1.1%. Meanwhile, the Seagate Barracuda Green had a whopping 120% annual failure rate (an average age of 0.8 years). While those were warranty replacement drives—likely refurbished ones already used—the other Seagate drives had failure rates between 3.8% and 25.4%.P

Overall, most of the drives survived for at least three years, but looking at this data, you might want to consider going with a Hitachi or WD drive instead of Seagate, unless you read other reviews of a specific drive's reliability.P