Verdict: For those with more cache than sense
Seagate used to lead the pack in hard disk technology. One of the first to produce 7,200rpm hard disks, the company has also regularly been ahead of competitors in terms of platter data density. But although Seagate was the earliest to claim support for NCQ in a few top members of its 7200.7 range, even the 7200.8 generation didn't offer full S-ATA II benefits. We've had to wait for the 7200.9 for that privilege, and it didn't materialise in time for our hard disk Labs test, putting Seagate behind a number of its competitors.
On paper, the new Barracuda has the potential to be a scorcher - or, at least, some members of the range have this promise. The 7200.9 is offered in sizes ranging from 40GB to 500GB, with between 2MB and 16MB of cache. Only the smaller-capacity EIDE models are available with 2MB of cache; the S-ATA models have at least 8MB, and drives of 300GB or larger in either interface sport the full 16MB. As is habitual with Seagate drives, the aerial density also varies enormously across the range. The 40GB model only has the previous generation's 80GB platters, while the 80GB and 160GB versions jump to 160GB per platter, and there are models with 100GB, 120GB, 125GB and 133GB platters as well.
This is all very confusing, as data density can have a huge effect on performance. Gone are the times when any member of a hard disk range could indicate the performance of the others in the range. Therefore, a review of one model should be treated as valid only for that one. Anything less than 200GB is a poor choice for future proofing these days, so the 300GB looks likely to be a popular seller, but that only offers 100GB per platter, which the top members of the 7200.7 range, such as our previously Elite-listed Barracuda 7200.7 200GB, already had. The 400GB version of the 7200.9 has more state-of-the-art 133GB platters, but this is only available with an EIDE interface. So we're left with the range-topping 500GB version, which at least has 125GB platters.
This is the model we ended up testing - also called the ST3500641AS, just in case you're confused by the plethora of choices. We attached the 7200.9 to our hard disk test rig, an Athon 64 FX-55 overclocked to 2.8GHz with an Asus A8N-SLI Deluxe motherboard and 1GB of DDR RAM. We used the Asus board's nForce4 S-ATA II controller, rather than the additional on-board Silicon Image controller, because it supports all the necessary S-ATA II performance features. We then ran our suite of performance tests.
Simpli Software's HD Tach 3RW's assessment of the 7200.9 wasn't particularly stunning. The average read sustained transfer rate (STR) of 50.2MB/sec across the disk was one of the slowest we've seen in a while, and write performance was even less impressive at 46.3MB/sec, although the 13.9ms average access time was relatively mid-range.
How this translates into the real world is more important, though, and here the 7200.9 had a bit more to offer. In particular, the Far Cry game level load showed the benefits of combining S-ATA II with NCQ and 16MB of cache. The 7200.9's average time of 51 seconds in our test runs was the fastest we've seen on this test PC, beating even our current Elite-listed Hitachi T7K250. And while the 7200.9's Paint Shop Pro benchmark score was noticeably slower than the fastest drives we've seen, it was on a par with the slower drives in our most recent Labs test. So the 7200.9 could be well suited to a gaming rig, and it would provide ample storage for lots of games. Seagate's Barracuda 7200.9 range isn't just about performance and capacity either. It's also environmentally friendly, with its lead-free production process meeting the European Restriction of Hazardous Substances (RoHS) certification.
CONCLUSION
As with all of the largest hard disks, the 500GB 7200.9's biggest downside is its price. At 51p per GB, this drive is more costly than Hitachi's equally massive Deskstar 7K500, and you could pick up three Deskstar T7K250s for the same money and have 50 per cent more capacity, or a more secure RAID 5 configuration. While the 7200.9 was extremely fast in our Far Cry level loading test, its performance was otherwise pedestrian. We had high hopes for the 7200.9, but it didn't turn out to be quite the 16MB cache cow we'd been waiting for.
