BACKGROUND:

Here's a little background on my WD drive experience, to provide context for the review. For my particular usage and review of this specific product, hop further down.

My previous experience with other WD drives have been anywhere between 100 and 500gb drives, typically the WD Caviar Black or Caviar Blue series which are stout (Black being preferred). To date I still use a 250gb Black model which is almost 10 years old and has been in very harsh conditions, ranging from 0*-130* Fahrenheit sustained ambient temperatures, and has been submitted to multiple shocks and shaking around while in use. Needless to say, it's a proven performer and a very solid platform.

Enter the Green drive era.

The WD Green drives boast lower operating temperatures and of being quieter, which they accomplish by on-the-fly adjustment of the RPM of the spindles, which uses less power and produces less heat or noise in the process. Essentially these perform no faster than 5400rpm (some have suggested 5900), rather than 7200rpm, and they will cycle off or go into a low power state at various times.

Some might wonder why such a large drive with "environmental" features, can be so inexpensive compared to the Blue or Black series drives of the same (or less) size. Basically it boils down to reliability. Do your research on the WD Green drives on a lot of tech sites and you'll find that the first generation units had lots of issues because of their "green" features. For example, my experience below

This is my 4th WD Green drive of large capacity, the previous three being 1TB units and first generation. Two of the previous three are also dead, I might add. These 3 previous drives were purchased back in 2010. The first one to die, did so within about a week of use.

It started having issues with it not wanting to come out of its powered-down mode, and shortly thereafter I started hearing the deadly "click.... click..." noise, indicating a head crash. The drive was unusable, and I later verified that the heads did in fact have a physical failure. I took the drive apart and found that when going into a low-power cycle the heads parked themselves too harshly or somehow went too far past the head park zone, so several of them got caught on the plastic locking lane. As soon as the arm tried landing on the platters, it ripped several of the heads off and scratched the platters.

The other drive, it's replacement and same exact model, died within about a month. Not a head crash, but was having intermittent spindle issues with not wanting to properly spin.

The third drive I've had ever since, and haven't had any major issues with it, but on a couple of occasions in the past year it has randomly powered down of its own accord (hard power down), and I lost some data.

HDD RPM SPEED 5400 or 7200:

If you're wondering which is better: 5400 or 7200, here's a little tidbit of info: The 5400 models spin slower, have a higher latency (seeking around the drive), but transfer more data overall. The 7200 models spin faster, have lower latency (can bounce around the drive faster), but provide less data per transfer.

What this means is, if you need a drive as your primary "program" drive, which will be doing frequent drive access and bouncing all over the place, doing work with many smaller files, then you'll want a drive with lower latency such as the 7200. On the other hand, if you just need a large storage drive for storing many large files, for example movies or other huge files, then a 5400 drive would be perfect.

Look at it this way, say you have a lot of small piles of leaves in your yard, and you need them bagged. If your bagger was a 7200, it could go from one pile to the next much faster than a 5400 could, but its performance benefits will be best with smaller piles. A 5400 would work best with fewer much larger piles.

SPEED SUGGESTION:

If you're concerned about overall speed and want this drive, once you have the majority of your files in place, run a good defrag tool every now and then to help keep all the files in sequence. This prevents the drive from having to bounce around so much. Also, WD provides a file alignment tool which you can use. They suggest using it once you have everything setup the way you want it. The link for this tool is on their website, and on the label of the drive.

MY USAGE OF THIS DRIVE:

The WD20EARX has so far, (a week into things), been very good to me. If you're curious about model designations, here's a couple of examples to help you while you search for your drive:

EARX - The SATA 6gb/sec (600MB/sec) interface (backwards compatible with slower SATA slots)
EARS - The SATA 1.5gb/sec (150MB/sec) interface

I'm using this as both a boot drive and a data drive, something I don't usually do but for my use I want only one drive in the system. It's going to store about 1.5tb of data, mostly in only a few files which are mostly 8-10gb in size each. Latency wasn't a concern for me, so the slower Green drive didn't bother me. Boot times and program loading has actually been surprisingly fast, faster than my other Green drive.

System: Shuttle XPC
Motherboard: SN95G5 - 2.6ghz Athlon64 - 2gb ddr2 ram
Interface: SATA 1.5gb (150MB/sec)
OS: Windows XP Pro SP3
Boot Speed: ~10 seconds (Once POST ends until I have a working desktop)

From the time the bootloader engages until the time I'm at a working desktop, it's about 10 seconds. Shockingly good performance for a green drive. Your experience may vary.

PROS:

* Large capacity, low price thanks to Amazon Prime

* Western Digital has a good reputation and warranty

* This newer generation green drive seems to be much better than the previous, including a redesigned PCB and power traces

* Full backwards compatibility with older SATA interfaces

* Includes a jumper spot in case you need to manually set SATA speed or go into technicians mode

* Lower power consumption, temperatures and sound signature, if that matters to you

CONS:

* Still worried about how the last few Green drives went

OTHER THOUGHTS:

* My past experience makes me uncomfortable with the Green drive movement, but I'm hoping they've worked out the kinks in this new redesign and will post any updates..

* Be aware that Windows XP will not be able to use a single partition larger than 2tb. Windows Vista or 7 will handle larger than 2tb at a time

Pros - This drive is awesome. Tested for over 24 hours without a hitch before format. Getting file transfer speeds between 130 - 115 mpbs.

Cons - none yet.

Other - Drive requires an advanced format partition. Must use xp jumper to use without proper setup. Advanced Format means the drive needs 4k sectors in order to read/write without errors. The drive partition must be aligned to a sector divisible by 8.

Running - Ubuntu 11.10
GUID partition table
EXT4 partition type
Aligned to 2048

This is a reliable, quite, cool running, LARGE SATA III HD. I used this drive for WMC (Windows Media Center) PVR. I needed a lot of hard drive space but needed it to stay really cool and quite in a small case. If you want speed (like I did) put a small SSD drive in your system for the operating system, then use the WD Green drive for storage space.

Something to consider: The 2.5 ad 3TB WD Green drives use a little bit more wattage (heat) and have a little faster transfer rate. Download the spec sheet from Western Digital for more information on this.

Just in case you're trying to do the same thing, I have listed my recently built media center parts list.

My system build (works great)(Photo's included)
-- SilverStone Aluminum/Steel Micro ATX HTPC Computer Case GD05B (Black)
-- Gigabyte AMD GA-A75M-UD2H (rev 1.0) Mother board
-- AMD A8-3850 APU with AMD Radeon 6550 HD Graphics 2.9GHz Socket FM1 100W Quad-Core
-- Kingston Technology HyperX 8 GB (2x4 GB Modules) 1600 MHz DDR3 Dual Channel Kit (PC3 12800)
-- OCZ Agility 2 OCZSSD2-2AGTE60G 2.5" 60GB SATA II MLC Internal Solid State Drive
-- Western Digital Caviar Green 2 TB SATA III Hard Drive - WD20EARX
-- Pioneer Internal 12x Blu-ray Disc/DVD/CD Writer BDR-206DBK
-- AmuletDevices remote control and IR Receiver
-- Antec (Neo HE650)(NeoPower 650) 650 Watt Power Supply
-- IOGEAR Multimedia Keyboard with Laser Trackball

I bought several drives recently to increase the storage on my HP MediaSmart server (EX470). The first drive I bought was 3TB, and after hours of trying to figure out why the server wasn't reading the full capacity of the drive, I found out it was not compatible. The 2nd drive was a seagate that was DOA. This was the 3rd drive I bought. After hours spent with the other drives, I was pleasantly surprised to see that I could pop this one in and there where no issues. Might be a little pricey, and it may not hold the most data, and it may not be the fastest drive, but the fact that it worked was good enough for me. If you are looking to increase the capacity of your 1st gen HP MediaSmart server, this is the drive for you.