We tested HD Tach with the benchmark's full variable zone size setting.
HD Tach's straight-line sustained transfer rate drag races aren't particularly indicative of real-world performance, but they're good measures of peak sustained throughput. The new 'cuda isn't quite quick enough to catch the VelociRaptor here. Still, it's a hair faster than the 1.5TB Barracuda 7200.11, which has a healthy lead over the rest of the field.
Given its denser 500GB platters, one might expect the 7200.12 to deliver much higher sustained transfer rates than the 1.5TB Barracuda. However, the 7200.12 only has two platters, which gives it much less outer-edge area than the four-platter 1.5TB 'cuda. Drives are at their fastestat least with sequential transferswhen accessing the outer edge of a platter.
In terms of burst rate, the Barracuda 7200.12's is a little slower than not only its direct rivals, but also its predecessors in the 7200.11 family.
Seagate's new 'cuda has by far the slowest random access time we've seen from a contemporary desktop drive, trailing the Barracuda 7200.11 1.5TB by two milliseconds and the Caviar Black by more than five milliseconds. That might seem like the blink of an eye, but within the GHz confines of a modern PC, it's actually a rather long time. Such is the price of the 'cuda's "quiet" seek mode.
Of course, seeking data gets more challenging at higher areal densities. However, the Caviar Green 2TB, which has 500GB platters and a much slower spindle speed of close to 5,400 RPM, achieves random access times two milliseconds quicker than the 7200.12 despite also being a very quiet drive.
The results of HD Tach's CPU utilization test are well within the app's +/- 2% margin of error in this test.