Question: 7200 RPM Western Digital Blacks are designed to be faster than Western Digital Blues/Greens.
They are the same speed, same cache, etc. What really makes them actually faster?
Does it have to do with spin up/down speeds or what?
Answer: The list of differences I managed to compile while shopping for Christmas was:
Blacks supposedly have dual processors, which apparently gives higher throughput and lower latency. They also have a five-year warranty.
Greens aren’t 7200 RPM drives. Western Digital lists them as “Intellipower”, which they originally claimed meant that they varied their speed dynamically from 5400-7200 RPM to help save power when not under heavy use. These claims were quietly replaced by a very fine print definition of each individual drive is manufactured with a slightly different speed. Independent testing has confirmed that they are ~5900 rpm drives. They also have a reputation for a high failure rate, especially early on and have only a two-year warranty. They have a “feature” where they park the heads after eight seconds of inactivity supposedly to save a little more power, but this puts more wear and tear on the drive and people generally recommend disabling it. Bottom line: stay away from these drives.
The Red edition is just a Green with the Time Limited Error Recovery (TLER) feature enabled in the firmware, and a little bit more QA before they go out the door, with a three-year warranty. TLER only matters for use in RAID arrays and really doesn’t seem to be very important to other users.
The “RE” RAID Edition are black drives with TLER and a five-year warranty, and high price. They are aimed at corporate servers that are always on and are always accessed.
The Blues are the run-of-the-mill average. I ended up getting three of these and put them in a RAID 10 for both speed and reliability, for less than the price of a 10,000 rpm VelociRaptor. The array pushes ~500 MB/s.