Conclusion

We have tested 2.5-inch hard disk drives based on 160GB platters and with a spindle rotation speed of 7200rpm. Of course, they are faster than HDDs of the same form-factor but with a spindle rotation speed of 5400rpm. The higher recording density of the 500GB Western Digital Scorpio Blue helped it leave last place in some tests but mostly due to its very good firmware. It was unable to catch up with the Western Digital Scorpio Black. The difference in power consumption between 2.5-inch drives with different spindle rotation speed is small: about 0.2W in idle mode and 0.5W under load. We are talking about HDDs with similar electronics and actuators, of course. It is quite possible to find a pair of models in which a 7200rpm drive will consume less than a 5400rpm one.

Comparing the participants of this review with the desktop 3.5-inch HDDs, the latter do not have too many advantages. They offer a cheaper cost of storage and large capacity, that’s all. They are not faster anymore. 3.5-inch drives are ahead of their 2.5-inch counterparts in linear speed, i.e. at operations with large files (and such files must not be fragmented). In all other cases, the lower response time of 2.5-inch products helps them compete and often beat their 3.5-inch opponents. Even the 5400rpm Western Digital Scorpio Blue is not much slower than them whereas the WD Scorpio is actually the overall winner of our tests. So, using a 2.5-inch drive in your notebook or desktop PC won’t limit your disk subsystem performance. Perhaps operations with large files will take somewhat longer, but at everyday applications such a computer may prove to be even faster than a computer with a large 3.5-inch drive. And of course, 2.5-inch drives are two and four times more economical than their 3.5-inch counterparts in idle mode and under load, respectively.

And finally, we’d like to say a few words about each model especially as they behaved very differently. The Seagate Momentus 7200.3 is one of the most economical drives in its class and its sequential speeds are the best in the 2.5-inch category (we don’t count in the WD VelociRaptor and models with SAS interface as they are meant for other applications). Unfortunately, this product’s advantages end here. Its firmware is not good enough and its heads are slow. As a result, it is often slower than its predecessor from the Momentus 7200.2 series.

The Western Digital Scorpio Black, on the contrary, has very good firmware that helped it win most of our tests (especially server-like loads). This product is actually free from serious drawbacks and we don’t feel like caviling at small things. Western Digital has made a good debut with this drive in the 7200rpm 2.5-inch product sector.

We are now waiting for Fujitsu and Hitachi to join the race and for the Seagate 7200.4 with 250GB platters to come to shops.