Apple released a new generation of Time Capsule last week. Contrary to speculation, there weren’t any major differences between the 2011 Time Capsule and the generations of old. Several rumor sites said that it would run iOS and cache Apple software updates for all of your devices… neither of those rumors ended up being true. In fact, Apple didn’t modify any components but the hard drives.
Overheating plagued the Time Capsule since its first generation: hard drives put out a considerable amount of heat… that overheated the power supply capacitors, made them bulge and eventually killed the device. We’ve been fixing time capsule power supplies and offering TC modifications to help prevent overheating for some time. Left in the stock configuration, all previous generations would die in about 18 months. Without any ventilation, Apple hoped the heat would dissipate through the bottom of the device to its surroundings. That wasn’t realistic with the power hungry hard drives they used in previous models.
In this new generation, Apple switched to Western Digital’s Caviar Green hard drives. The drives operate at cooler temperatures with less power consumption. Unfortunately, these drives are cheap, average drives instead of “server-grade” which Apple advertises. We went back through all of our original Time Capsule drives and found these:
- HITACHI Deskstar 7K1000 HDS721010KLA330 – shipped in the 1TB Time Capsule
- Western Digital Caviar Blue WD5000AAKS 500GB – shipped in the 500GB Time Capsule
- Seagate Barracuda ES ST3500630NS 500GB – shipped in the 500GB Time Capsule
The Seagate drive is the only one considered “server-grade.” Apple obviously installed multiple drive types into each generation of Time Capsule… not all of them were server-grade. Hardmac recently brought this to light — it’s getting a lot of attention right now — but it doesn’t appear to be a new development. Please continue reading to understand why this is a good move for Apple.
What constitutes server-grade?
Any drive that sustains one million hours as a mean time between failure (MTBF) qualifies as server-grade. Oddly, Western Digital will not comment on the MTBF for the Caviar Green drives. Maybe Apple knows something we don’t. We don’t consider this Caviar Green drive server-grade. In fact, Apple’s using one of the cheapest drives on the market:
- Western Digital Caviar Green WD20EARS 2TB – currently shipping in the 2TB Time Capsule
That drive is anything but awesome from a reliability standpoint. Many reviews report a high failure rate — even a high DOA (dead on arrival) rate — with these drives. Every hard drive has a percentage of DOA and early failures. Most of the time, it’s between five and ten percent but the reviews report a failure rate of nearly 25 percent. Yikes. While browsing around online, we found that Western Digital claims long-term reliability on some of their drives… but this isn’t one of them.
Why did Apple switch drives?
Heat. We’re not sure why Apple still advertises, “server-grade” on the Time Capsule specifications… but we’re happy that they’re using a cooler drive. A cooler drive means less overheating; less overheating means less power supply failures. From a repair perspective, it’s easier to replace a TC hard drive than TC power supply capacitors. We’re not excited about the circumstances, but at least Apple addressed a 3-year ongoing issue. We’ll take it.