We found out a lot of interesting information about the 250 GB hard disk drives available on the market today. In summary, not all 250 GB drives are equal.

For example, a higher buffer size doesn’t mean a higher performance. On units from Seagate we didn’t see any performance increase by using a model with 16 MB buffer, while with Western Digital models we could clearly see a performance boost in some tests.

The average user will be good with a Seagate Barracuda 7200.10 ST3250310AS, which in our opinion is the drive that provides the best cost/benefit ratio for the average user from all nine 250 GB drives we tested. Maxtor DiamondMax 21 is the same drive with a different label, but at least at Newegg.com it is a little bit more expensive. This Maxtor model is also a great buy if you can find it for the same price or less.

Here is a breakdown of what we found out about each hard drive included in our round-up:

• Hitachi Deskstar P7K500 (HDP725025GLA380): Achieved a lower-than-average performance in our round-up. Don’t buy.
• Hitachi Deskstar T7K500 (HDT725025VLA380): The worst hard disk drive from our round-up, with a performance far lower than all other drives. Don’t buy. If you have one, replace it.
• Maxtor DiamondMax 21 (STM3250310AS): It is a Seagate Barracuda 7200.10 ST3250310AS with a different label. Great performance for the average user. Buy this Maxtor model only if you can’t find Seagate Barracuda 7200.10 ST3250310AS or if it is cheaper than this model from Seagate.
• Samsung HD250HJ: The results for this drive varied according to the program we used. It achieved the same performance level as the recommended Seagate Barracuda 7200.10 ST3250310AS on HD Tach and HD Tune, but a lower on DiskSpeed32. That is why we are recommending that model from Seagate over this model from Samsung.
• Seagate Barracuda 7200.10 (ST3250310AS): As mentioned, provides the best cost/benefit ratio for the average user. This is the 250 GB hard disk drive you should buy.
• Seagate Barracuda 7200.10 (ST3250410AS): It provides 16 MB buffer instead of 8 MB, but on our tests this bigger buffer didn’t increase performance, achieving the exact same performance of the above model. Since it tends to be a little bit more expensive, buy the above model instead.
• Seagate Barracuda ES (ST3250620NS): This is an “enterprise” model being more expensive than the other tested drives. The problem is that it was faster than the other drives only on DiskSpeed32 burst transfer rate. This is a good example that a more expensive drive doesn’t mean a faster product. Don’t buy.
• Western Digital WD Caviar SE (WD2500AAJS): Achieved a performance lower than the recommended Seagate Barracuda 7200.10 disk and costs the same thing. Don’t buy.
• Western Digital WD Caviar SE16 (WD2500AAKS): Its 16 MB buffer improved the performance over the above model, but while it was faster than Seagate Barracuda 7200.10 on DiskSpeed32, it was slower on HD Tach and HD Tune. That is why we are recommending that model from Seagate over this model from Western Digital.