Hard disk roundup: every category tested
Darien Graham-Smith
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Oct 27, 2008 2:31 PM
High-capacity desktop drives have never been so affordable. Darien Graham-Smith puts 23 to the test to find the best
It’s 35 years since IBM introduced the first modern-style hard disk, the 3340 Direct Access Storage Facility – the ‘Winchester drive’ to its friends – with a capacity of 35MB. Today, that seems laughably small: modern PCs tend to come with a drive capacity of hundreds of gigabytes.
But while modern PCs may have huge storage capabilities, it’s also easier than ever to fill that space. Installing Vista eats up around 7GB before you even run a program. Applications and games have grown too: Office 2007 needs 1.5GB of space, while Crysis recommends 12GB. Adobe Creative Suite CS3 officially requires a mammoth 22GB for a complete installation.
The real space-hog, though, is media files. The modern PC is increasingly a hub for digital music and video, and a media library can easily devour tens or even hundreds of gigabytes.
If you use a PC for editing your own videos you can very quickly generate gigabytes of raw footage and working files as well.
The good news is that extra storage is more affordable than ever. Back in the 1970s, you could find yourself paying $75 or more per megabyte of hard disk space. Today’s 3.5in desktop drives work out closer to 20c per gigabyte – a phenomenal price drop, even before you take inflation into account.
What’s more, while prices have dropped, capacities have gone through the roof. All the major hard disk manufacturers now offer drives capable of storing an immense 1,000GB – one terabyte – of data. So whether you’re building a new desktop PC or adding a second drive to an existing machine, there’s definitely no need to skimp on storage.
But which drive is best for you? This month we take a comprehensive cross-section of the high-capacity 3.5in SATA hard disk market, from 500GB upwards, examining major models from all four main manufacturers, to help you identify the perfect drive.
The categories
Over the coming pages, you’ll see we’ve divided this month’s drives into three categories. The first category is Value drives. Put simply, these are the models that will appeal if your first concern is your budget: they’re the cheapest disks here, and while you won’t get a full terabyte for this sort of money, there is a 640GB model and even a 750GB drive available for well under $200.
The second category is Mainstream drives. These are drives for those willing to spend a little bit more than the minimum, perhaps to get a performance boost or the maximum possible storage space. We look at the benefits each drive offers and consider whether those benefits are worth the price premium.
Finally, we come to Specialist drives.
Some are intended to keep noise or power consumption low, while others are optimised for a server workload. We put each drive through its paces to see how it walks the walk.
How we test
Although we’ve divided our drives into three broad categories, each unit, regardless of category, is subjected to an identical series of tests and calculations to identify its strengths and weaknesses. You’ll see the results summarised in the graphs on the following pages, along with tables detailing each drive’s physical characteristics and purchase information. We go into further technical detail in the main text as well.
Our first test involves measuring each drive’s performance. The speed at which a drive can read and write data is affected by a number of factors, including the size of its RAM buffer and the number of platters it uses. You’ll find details like this in the feature tables.
However, as our test results show, physical characteristics alone give only a very rough guide to performance. Therefore, we subject each drive this month to a battery of synthetic and real-world tests.
For our first test, we run our real-world application-based benchmarks on a standard system, using each disk as the system drive.
Then we use Simpli Software’s HD Tach application to measure each drive’s sequential, random access and burst read speeds, giving us the upper bound for each drive’s potential.
Finally, we combine the results – weighting our real-world benchmark results more heavily than the artificial measurements – to express each drive’s overall performance as a percentage of the average across all drives. This figure is given on the graphs on the coming pages.
We also measure each drive’s idle power consumption. Since Windows’ many background services cause constant fluctuations in the amount of power used, we measure total power consumption for a system sitting idle at the BIOS screen, then subtract the power draw observed with no drive attached. Even under these circumstances, power draw constantly wobbles up and down within a margin of one or two watts, and to counter that we take multiple readings over a 30-second period and record the average power draw with each drive.
Finally, we measure the noise generated by each disk. Each drive
is installed in a completely silent Home Server system. The system is then placed in a soundproof environment and precise acoustic measurements are taken, measuring the drive both when spinning idle and when read and writing data.
The tests are carried out by the independent testing centre Intertek.
We then weigh up all this in light of the drive’s value for money – not just its purchase price, but its cost in terms of cents per gigabyte of storage. Remember, though, that the hard disk market is a fast-moving one, so this calculation of value won’t hold forever.
Having taken all these factors into account, we award each drive a star rating out of six, indicating which models make for a great buy and which are better avoided.
Ratings explained
The star ratings you’ll find within each feature table are relative only to the products on test in any particular Labs. A one out of six rating doesn’t mean the product is the worst of its type to be made, just the least impressive that month. Likewise, a six out of six score isn’t necessarily an indication of perfection.
Attractively priced drives that boast surprising capacity and performance levels
If you want a high-capacity drive on a budget, you expect to compromise. But today there are some remarkable drives available for $150 and under, and from some brands that may surprise you.
For example, the Western Digital Caviar SE16 is advertised as a ‘high performance’ drive, but two models from the range fall into our budget price bracket this month – a 500GB and a 640GB disk. Their 16MB buffers indicate that they’re not really top-end parts – these days 32MB is where it’s at – but they work out at a reasonable 19.8c and 16.4c per gigabyte respectively.
But it’s very much a case of buyer beware.
The headline specifications suggest these drives are identical but for a small matter of 140GB. However, in reality there’s a huge difference in performance. The 640GB model is the best overall performer in its price range, achieving a very creditable sequential read rate of 118MB/sec and putting in a strong showing in our multi-applications benchmark, finishing the test in a nippy 4mins 41secs.
The 500GB version achieved nowhere near these levels of performance. Its maximum sequential read rate was just 80MB/sec, slower than any other drive in this category, and it took 12 seconds longer to complete our multi-apps benchmark than its faster brother.
The explanation for this striking discrepancy isn’t hard to find, if you know where to look. Inside the casing, the 500GB Caviar SE16 contains three physical disks (or platters), each one capable of storing 166GB of data. The 640GB model uses just two platters, packed far more densely with data to give them a capacity of 320GB each. Since all of these disks spin at the same speed of 7200RPM, it’s only logical that the more sparsely populated disks will transfer data at a slower rate.
The upshot is that the 640GB is a decent buy, giving first class performance at a fair, if not exactly bargain basement, price. The 500GB model, however, is best avoided.
Seagate
Another name we didn’t expect to see in this category is the Seagate Barracuda 7200.11. But the 500GB version comes in at just $95, and boasts all the grown-up features of the larger models, including a 32MB buffer and – uniquely at this price – a five-year warranty.
Its platter capacity of 250GB isn’t ground-breaking, but it is above average, and that allowed it to achieve satisfactory performance in our tests. Sequential read speed was particularly good at 116MB/sec, and its random access seek time was among this month’s quickest at any price.
This didn’t translate into a great real-world benchmark score, though, with the multi-applications result disappointingly average. Burst read speed was poor, at around 130MB/sec – less than 60% of some of its rivals. Still, power consumption was low at 6W, and with the warranty it’s a good deal.
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| Value drives: benchmarks |
Value Drives
Maxtor
Seagate is also the manufacturer of the Maxtor DiamondMax 22 series of drives, the 500GB version of which comes in at an almost identical price to the 7200.11 and offers identical physical specifications.
There may be some minor technological differences – it’s noticeable that Seagate doesn’t extend Barracuda buzzwords like ‘clean sweep drive calibration’ to its Maxtor marketing. But we’ve yet to detect any real-world benefit to those technologies, so we wouldn’t be overly concerned over their absence.
Predictably enough, the DiamondMax 22 performed exactly the same in our tests as the 7200.11, to within one tenth of one per cent. It achieved the same excellent sequential read score and the same middling benchmark score, while burst access was just as weak. Power consumption was the same as well.
But while there’s nothing exactly wrong with the DiamondMax, its three-year warranty doesn’t make a lot of sense when you can get the functionally identical Barracuda 7200.11 with a better warranty for only a touch more.
Hitachi
The Hitachi Deskstar P7K500 is another high-end name that sneaks into the value category in its 500GB form. It’s a perfectly capable drive, with two 250GB platters but only a 16MB cache. Its 7W power draw is lower than most, which is a plus, but performance is a mixed bag. Sequential read speeds peak at just 94MB/sec, and seek time was one of the slowest here.
Benchmark scores were the lowest in this category too, with the multi-applications test taking 4mins 54secs with this drive – eight seconds longer than the group average.
The Deskstar did, however, achieve an excellent burst speed of 239MB/sec, which, depending on your usage, could compensate for the slow seek time. But there are better all-round performers out there for the same money.
Samsung
Lastly we come to a trio of drives from Samsung. The 500GB Samsung SpinPoint T has long been a firm favourite at PC Authority, but technology keeps marching onward, and its 166GB platters are now starting to look rather outdated. Its performance, which once impressed us, is now behind the curve, and though the pricing is excellent (working out at just 16.2 per gigabyte) it’s clear that this venerable unit is well past its prime.
Thankfully, its replacement is already here: the SpinPoint F1 DT range includes a new 500GB drive and, remarkably, a sub-$150 750GB unit. Both use 250GB platters, though the smaller drive has only a 16MB cache. Sequential read speeds are nothing to write home about, peaking at 93MB/sec, but burst speeds are exceptional at 241MB/sec.
When it comes to real-world performance, both drives achieved excellent scores, with the 500GB version’s smaller cache doing it no measurable harm at all. Both completed our multi-applications test a whopping seven seconds ahead of the group average.
And power consumption is really the icing on the cake, with the 500GB unit drawing just 5W and even the 750GB model demanding only 7W.
In the face of results like this, the only question is which model to go for. The 750GB drive is exceptional value, working out at just 13.7c per gigabyte; but the 500GB unit isn’t bad, costing 17.4c per gigabyte, and gets you a whole lot of space plus great peformance for a very small outlay.
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| Value drives: full specs table |
They're bigger, faster and more expensive - but which are really worth the extra investment?
If you’re willing to dig a little deeper into your pocket, there’s a range of drives available offering more capacity, and often better performance, than their cheaper counterparts.
Smack in the middle of this price bracket, at $224, is the DiamondMax 22 1TB, made by Seagate but sold under its Maxtor brand. This drive is fundamentally the same as the budget 500GB unit, but where the smaller drive uses two 250GB platters, the 1TB unit uses four. The extra platters drive up power consumption to 9W – which is on the high side of this category’s average.
Unsurprisingly, these two drives perform almost identically to their smaller brother, and that’s not a bad thing – 250GB per platter translates to one of the highest areal densities available, and the DiamondMax’s read speeds peak at 115MB/sec at the outer edge of the disk, falling to around 50MB/sec at the centre. This confirms that DiamondMax drives are great for streaming. Unfortunately, this unit also shares the 500GB’s comparatively low burst speed of around 130MB/sec.
These mixed results translate to mixed real-world performance, with the DiamondMax drive achieving below-average scores in our multi-apps test. However, it’s important to note that, in this category, the variance for this benchmark was small, with just 13 seconds separating the fastest and slowest drives over a test lasting almost five minutes.
So while they’re not the best overall performers, the DiamondMax 22 drives remain fast enough for all but the most demanding roles. What’s more, at 22.4c per gigabyte, the 1TB model represents decent value for money.
Seagate
Seagate also competes in this category under its own name, with the Barracuda 7200.10 and Barracuda 7200.11 series. 750GB versions of these drives can be had for $298 and $166 respectively – and, as the prices might suggest, the 7200.11 is by far the more desirable. It shares the Maxtor’s 32MB cache and 250GB platters, and in our tests it achieved the same strong – if not award-winning – performance.
The 7200.10, meanwhile, offers only a 16MB cache, and a lower areal density due to its use of 187GB platters. Unsurprisingly, this has a measurable impact on performance. The 7200.10 came towards the bottom in every one of our speed tests, with its random access seek time of 20ms a particular low point. Maximum sequential read speed was just 82MB/sec and burst rate was on a par with the Maxtor’s poor 130MB/sec. Predictably, for a four-platter drive, power consumption is high too, at 9W.
One distinctive plus both drives enjoy is a five-year warranty. Naturally, Seagate won’t recover your data for you, but it’s still more peace of mind than you’ll get with most brands. Seagate claims built-in G-force protection too, though we hope few of our readers are in the habit of dropping desktop drives on the floor.
Overall, the Barracuda 7200.11 is an appealing drive, but unless you’re wedded to the warranty it’s hard to justify choosing it over the Maxtor. The 7200.10, meanwhile, makes no sense at all: give it a miss.
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| Mainstream drives: benchmark results |
Western Digital
You might also be tempted to skip over the 750GB Western Digital Caviar SE16, since it shares the 7200.10’s 16MB cache and four 187GB platters. This sort of arrangement is unremarkable in the value segment, but at this higher price it augurs ill.
Yet the 750GB SE16 shames its rival by faring far better on the same specs. In our tests it delivered a creditable burst read speed of 219MB/sec, some 70% faster than any Seagate. In the multi-applications test the Western Digital tied for first place in this category. Sustained read speed is below par, however, peaking at 101MB/sec at the platters’ outer edge before dropping off to 46MB/sec at the centre.
The price is good too, working out at 22.5c per gigabyte. It’s a pleasant surprise, though overall performance is still too average for us to recommend the SE16 unequivocally.
Hitachi
Raising the budget bar once again, we come to Hitachi’s Deskstar 7K1000, in both 750GB and 1TB variants costing $174 and $248 respectively. These drives promise a special low-power idling mode, and in our tests we saw average idle wattages sit at 8W and 9W. Not bad considering that these drives use 200GB platters, meaning the larger unit contains a whopping five disks.
Despite the Hitachis’ comparatively high price, sequential read scores were disappointing, with both units peaking at 88MB/sec and falling off to 44MB/sec. Burst rates, however, ran up to 212MB/sec, and both achieved very similar seek times – the quickest of any mainstream drive. This helped the Deskstars fare better in our real-world benchmarks.
Ultimately, though, the price just isn’t right, with the 750GB model working out at 23.2c per gigabyte, and the 1TB model nearing 25c. Although that’s not much steeper than other drives on test, nothing about either drive justifies paying that much.
Samsung
Finally, we come to our category winner, the Samsung 1TB SpinPoint FDT. It already occupies a well-deserved space on our A List, but this month’s tests confirm just how far ahead of the competition Samsung’s little marvel is. The Korean manufacturer has managed to cram 1GB onto just three platters, slashing power consumption to 7W while ramping up areal density to deliver first-class performance.
The proof of the Samsung’s excellence is in the results. The SpinPoint’s maximum 124MB/sec sequential read speed is the fastest of any drive this month. Its burst speed of 237MB/sec is the best in its category, and within 2% of the best overall. And in our multi-applications benchmark it tied with the 750GB Caviar SE16 for – you’ve guessed it – first place.
At its launch four months ago this drive would set you back $300; it can now be yours for just $200. That works out at 20c per gigabyte: astonishing value for a terabyte drive and better than almost all of its competitors. If you have the budget, it’s hard to see why you’d pick anything else.
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| Mainstream drives: full spec table |
Quiet drives for media centres, low-power units and enterprise-class server disks
If you’re looking for a drive for a particular purpose, there may be a model designed specifically to suit that role. For example, a drive inside a media centre should be quiet and, since it’s likely to be switched on most of the time, reliability and power consumption are of particular concern too.
Unfortunately, despite its name, the 500GB Western Digital AV Edition is probably not the answer. Spinning idle, it whirred around at 22dBA – not crashingly loud, but it’s far from this month’s quietest drive. And when seeking back and forth, sound levels went up to 25dBA – on a par with this month’s noisiest units.
Power consumption was unimpressively high too at 9W, but it was performance that really sealed the AV’s fate: though its average score may look respectable, it achieved a top sequential read speed of only 90MB/sec, dropping down to a poor 38MB/sec towards the centre of the disk. Burst speed was on the low side too, at 200MB/sec, while seek time turned out to be surprisingly pedestrian at 17.1ms. In all, it’s impossible to recommend the AV Edition for a media centre or any other purpose – despite the comparatively low price.
The Western Digital Caviar GP series performs only slightly better. All three high-capacity variants use 250GB platters, which ought to deliver an immediate speed boost – but in our tests, sequential reads still failed to top 100MB/sec, and fell to the same 38MB/sec minimum. Real-world benchmark scores weren’t significantly better either, though they rose as capacity went up. The 500GB model actually lagged behind its AV counterpart in our multi-apps test, despite the larger cache (16MB against the AV’s 8MB).
But while the AV lacked any kind of saving grace, the GP series has more than one trump card up its sleeve. GP stands for Green Power, and these drives use variable speed motors to cut power consumption when possible. This reduced idle power consumption to just 5W, which gives it a power draw of some 30% below the average. Of course, hard disk power accounts for only a small proportion of a PC’s total power consumption, but every little helps, especially if you’re running multiple drives over an extended period.
What’s more, the GPs are this month’s quietest drives, with the larger capacity models registering just 17dBA when idle (anomalously, the smaller model was measured at 20dBA). Since decibels are logarithmic, doubling every ten units, this translates to a very audible difference between this and the noisier mainstream drives. Even when seeking back and forth, noise levels peaked at 23dBA for the largest drive, and around 20dBA for the lesser ones.
All of which makes the Caviar GP series a serviceable choice for a media centre or low-power PC, so long as you don’t need a drive for super-fast streaming.
The prices aren’t enticing, though – 22.8c per gigabyte for the 500GB model is more than you’ll pay for a mainstream drive, but the 1TB model is a more affordable 22.2c per gigabyte. The 750GB model, at 22.5c per gigabyte, sits, not surprisingly, between the two in price.
If media isn’t your bag, there are also drives designed specifically for use in a server or NAS device, such as the 500GB Western Digital RE2 and the 1TB Western Digital RE2-GP. The RE acronym stands for RAID Edition, and these drives are advertised as ‘enterprise class’ units, with enhanced vibration tolerance and a mean time of 1.2 million hours between failures.
Since Western Digital doesn’t publish MTBF figures for its other drives it’s hard to quantify the advantage, especially as it’s impossible to test meaningfully; but the company is at least confident enough in the RE2 to offer a five-year warranty, rather than the three year one with the Caviar models.
The RE2 and RE2-GP are fundamentally the same, except that the GP model uses the same power-reducing features as the Caviar GP, keeping its idle power consumption down to 5W while the standard RE2 drew 9W. Both drives use the same platter and cache configuration as their Caviar GP counterparts, so it’s no surprise that peak and minimum sequential performance is all but identical across the ranges.
The RE2-GP also achieved very similar benchmark performance to the Caviar GPs, but the RE2 raced ahead to achieve this month’s best test results. Unfettered by power concerns, it managed a multi-applications test time of 4mins 41secs, nine seconds faster than the RE2-GP.
These drives are quiet, too: we measured the RE2 at 21dBA when idle, rising almost imperceptibly to 22dBA when in use. The RE2-GP’s low-power circuitry kept noise down to 19dBA when idle and 21dBA when seeking.
As always with specialist drives, there’s a price to pay, but at 24.8c per gigabyte the RE2 is a good choice for an NAS device, especially in light of the generous warranty you’ll get to cover it. The 1TB RE2-GP works out at 27.5c per gigabyte, though, which is harder to swallow.
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| Specialist drives: bechmarks table |
Seagate
But if you’re looking for an enterprise-type desktop drive, Western Digital isn’t your only choice. Seagate has its own range, in the form of the Barracuda ES.2. It’s aimed at exactly the same market as the Western Digital RE2 drives, boasting ‘best-in-class reliability’ and it comes with a five-year warranty. It even claims an identical 1.2 million hours MTBF.
Performance is impressive. Its 250GB platters provide no greater areal density than the competition, yet in our tests these drives achieved better sequential speeds, reading over 110MB/sec and – perhaps more usefully – never dropping below 50MB/sec, regardless of the area of disk being accessed.
Real-world benchmark scores, however, were rather average, perhaps thanks to a low burst rate of just 125MB/sec. Since the ES.2s have twice the RAM buffer of the RE2s, it’s clear that buffer size is no sure guide to performance when choosing a hard disk.
The ES.2s’ PowerTrim feature is claimed to dynamically moderate power draw, but both units we tested idled at 8W, some way off the RE2-GP’s 5W. Nor is quietness a particular strength – the three-platter 750GB model registered 22dBA, whether idle or seeking, while the half-terabyte version registered 23dBA – an illogical difference, but minor enough to ascribe to the margin of error inherent in such measurements.
At 22.4c per gigabyte for the 500GB version and 30.5 for the 750GB model, it’s not a budget option, but the ES.2’s low seek times and high streaming speed suit it well to remote storage where noise and power are secondary concerns.
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| Specialist drives: bechmarks table |