Picking A Hard Drive For Your NAS: New Green Beats Old Speed

Drive Choice: Performance Or Eco? Spinpoint T166 Vs. F2EG

The Performance Option: Samsung Spinpoint T166 (HD321KJ)

We’ve been using Samsung’s Spinpoint T166 (HD321KJ) drives in our NAS tests for a while now. Originally, we picked this model because it offered high data transfer rates (for its time) while remaining affordable. Their capacity of only 320GB (definitely modest by current standards) actually works in our favor today, as it helps keep the time for some of our tests down. Besides, a higher capacity also means longer build times when initializing a RAID array. Believe us, waiting 24 hours for a terabyte of RAID storage to finish a build is about as much fun as watching the proverbial paint dry.

But let’s get back to the drive. Like all SATA/300 drives, Samsung’s HD321KJ supports both native command queuing (NCQ) and hot-swapping. It spins at 7,200 RPM and sports 16MB of cache as a buffer. To reach its nominal capacity, it employs two platters of 167GB each.

Peak data throughput comes in at 83 MB/s, although the hard disk performance benchmark h2benchw measured about 64 MB/s for both reads and writes. For reference, current 3.5” desktop drives can push about 120 MB/s. On the other hand, the RAID configurations found in most modern NAS servers are limited more by their processor than the hard drives, so even slower drives don’t usually become a bottleneck.

In the context of this comparison, the Spinpoint T166 is also a good reference point for users looking to upgrade an older NAS with newer drives. Aside from the obvious benefit of providing much more capacity, newer drives also tend to consume less energy.

The Eco Option: Samsung Spinpoint F2 EcoGreen (HD103SI)

Our other drives were also provided by Samsung. We opted for the Spinpoint F2 EcoGreen (HD103SI). Like the HD321KJ, this terabyte drive is built using two platters, each of which can store 500GB of data. Unlike the T166, the F2 EcoGreen is a current-generation drive, meaning that there are also some other notable differences.

Like its older sibling, Samsung’s HD103SI supports NCQ and uses the SATA/300 interface. However, the newer model sports 32MB of cache, twice as much as the T166.

At the same time, Samsung has dropped the spindle speed from 7,200 RPM to only 5,400 RPM in order to achieve the drive’s ambitions where low power consumption is concerned. Nonetheless, the drive achieves sequential read and write speeds of around 84 MB/s, while its maximum throughput comes in at over 100 MB/s. That’s not bad at all, considering the comparatively low spindle speed.

A Look at the Hard Drives

Spinpoint T166Spinpoint F2 EcoGreen
Model Number
Form Factor
3.5" 3.5"
Rotation Speed
7,200 RPM5,400 RPM
Other Capacities
80, 160, 500GB 500, 1500GB
16MB 32MB
SATA/300 SATA/300
Ambient Temperature
0-60°C 0-60°C
Power Consumption "Idle"
 (according to the manufacturer)
7.6W 4.6W
Shock Test (2 ms, read)
63 G
70 G
3 Years
3 Years
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  • Anonymous
    Is it a good comparison between 320 GB drives and 1 TB ones? Of course de 1 TB will perform better: much higher data density means less movement of heads and platters for the same amount of data. Gotta be faster. Nothing to do with the enclosure.

    Also I would like to mention from my own experience that heat can be a problem. I have a D-Link DNS323 and it cannot handle two server edition WD drives - it overheats.

    - Bertus.
  • evongugg
    If you buy a NAS, it's better to use the recommended drives, which have been put through hard tests.
    Other drives may experience RAID problems, burnout problems, etc.
    If you want to salvage a NAS hard drive, you may be dealing with a Linux type partition.
  • Anonymous
    Weird concept to compare an "old" performance drive with a new eco drive, where by default the new eco drive is outperforming the old performance drive in all categories.
    What is the expected result? Yes, we guessed right, the new eco drive is outperforming the old performance drive in a NAS environment.
    Unfortunately that comparison does not allow any conclusion whether a NAS needs a performance drive or not, it only tells us that a new eco drive is better than an old performance drive.
  • awaken688
    Totally agree with "theaxe" on this one. Not sure what this proved other than if you choice is an old performance drive vs. a new green one, choose the green one. Show me the WD 1TB Caviar Black vs. an equivalent "green" 1TB drive and then we can see more of a comparison that means something.
  • cknobman
    good thing we have the comments section so I dont wast my time reading a pointless article. first thought is "why in the f would you compare a 320gb to a 1gb?" reading the comments let me know my thought is right and not to waste time reading a pointless article.
  • chunkymonster
    Our comparison showed that the difference in write performance between faster and slower spinning hard drives is minimal to nonexistent when they are used in a NAS. Instead, the NAS’ RAID engine becomes the limiting factor.
    Ok, I can understand the RAID engine being the limiting factor when using off the shelf NAS solutions, especially considering most off the shelf NAS solutions use software RAID. But, would a 5400RPM drive become the limiting factor, compared to a 7200RPM, when using a hardware RAID solution like an Areca, 3Ware, or HighPoint controller card? Any guesses?
  • davidhbrown
    I've been reflexively buying 7200RPM drives for everything (notebooks, NAS, desktops) for so long now, that just the *concept* of the article is a useful reminder that in some settings, other issues might be important. Too bad the specific comparison may be flawed, but it's not like exactly that hardware is going to be relevant in six months anyway.
  • Anonymous
    Even with a 10 watt difference, the electricity savings is negligible. At the nation average of 12 cents per kWh, using 10 less watts 24/7 for a year works out to be a whole $10.50. On the year. Less than $1 a month. A far cry from what the article stated: "the difference jumps into the two-figure range. And that can definitely make a difference when the time comes to pay your electric bill" I'll take that 88 cents I save a month and go buy...wait, what can you get for 88 cents these days?
  • farrellj
    Just one thing...many consumer NAS boxes run a cut-down form of Linux...and Samba! And that makes it much more stable than some proprietary software that hasn't been as extensively tested as Linux/Samba has.
  • farrellj
    Just found out...the Synology DS409+ does use Linux!
  • icepick314
    i read somewhere that you should use green drives specifically made for RAID since it has option to change time-out period...

    otherwise NAS would think the drive is dead and give error if the drive went to sleep...

    is this wrong?
  • hixbot
    icepick314 that's kinda wrong. You want TLER for raid mirror arrays because yes the raid controller might thing the drive is dead and start rebuilding. If you use a mirror array in a NAS, then yes, you want TLER. but NAS aren't always configured with a mirror array, or use RAID at all (though they often do).

    the WD greens are not recommended for linux, which is used in most NAS. the greens still have a head parking issue, they have masked that issue with the latest firmwares, but not corrected it.

    There are still no decent eco drives for NAS in the 2tb space.
  • Anonymous
    I read that Synology's devices don't sleep. Is there a competing NAS that does sleep (and comes back via wake-on-lan)? That would save much more power than drive choice could.
  • Computer_Lots
    I could have sworn I read an article right here at Toms that showed 1TB green drives outperforming this exact Samsung T166. I believe that the point was the higher density plus the more efficient design made the newer 5400 rpm drives perform faster than older 7200 rpm.

    Really, You don't have a 7200 RPM 1TB drive laying around to test?
  • scooter69
    Is some one trying to tell us to use "green ECO drives"? Save a blade of grass or something.Sorry had to get it out. I agree with theaxe and cknobman on this one. You can't really compaire the two. Also with the ECO "green drives", I've heard that they don't always spin-up fast enough and fall out of the RAID setup and causing it to crash at times. Am I right, or wrong?
  • False_Dmitry_II
    I have a problem with the whole preface of the article. Is it kinda annyoing to do it yourself? Sure, but these kinds of devices cost over $100, and that is too much for someone like me.

    The majority of these features that are mentioned (with the notable exception of print serving, which can be added) can be had by installing FreeNAS. I took an ancient comp, slapped a SATA PCI card in it, and had it running in 10 minutes doing everything. Including serving my xbox 360 with music!

    I then proceeded to install linux instead so I could do crazier things like make the scanner accessible on any computer and of course printing too. It seems to be doing a pretty admirable job for what it is.
  • scooter69
    THANKS False_Dmitry_II, I've been thinking about using my one year old gutted maching for a over-sized NAS. My work doesn't like it much when I hyjack software and key codes. Now I have a reason to keep my older machine.
  • midnightgun
    farrelljJust found out...the Synology DS409+ does use Linux!

    Far as I know, all Synology products use the same version of operation system. A scaled down, specialized version of Linux. I've had a 407e for about a year and it has worked flawlessly and is so easy to manage.

    For those that don't want to spend the money on a cage, and have an old machine kicking around there is always the Freenas option (http://www.freenas.org/) which I hear works well.

    As for this review... Mixing old and new drives in a comparision not designed to see the difference in old and new drives seems... Well pointless.
  • chunkymonster
    Someone got down vote happy and gave a large number of posts a -1, interesting...
  • Anonymous
    Opening paragraph from your article from April:
    "If you're in the market for a storage upgrade, you have some important decisions to make. First off, there's the choice to build your own solution or buy one from an established vendor. If you choose the former path, know that there are tons of options, which we'll explore in a future story. Here, we'll be going down the latter path."
    How far into the future are we talking? Obviously longer than six months. That would be an article I'd like to read.