Hitachi Travelstar 80GN (IC25N080ATMR04)
I guess there is no need to remind you that many hard disk drives produced by Hitachi have been handed over to it by IBM. This drive is no exception, too. It belongs to the Travelstar 80GN family. The capacity of our disk was 80GB and it is the maximum storage capacity for present-day 2.5” HDDs. The capacity is made up by two 40 GB platters. The spindle rotation speed of 4,200rpm is the starting point, according to today’s standards. The cache-buffer size is 8MB. Note that two junior models from this family (of 40GB and 20GB storage capacities) have a 2MB buffer.
Hard disk drives from IBM have always been a mixture of original technologies. For example, the one we benchmark today features the following.
A special antiferromagnetically-coupled (AFC) layer helps to increase the data density per platter. In the long run, this technology allows to reach a data density of 100Gbit per square inch. It equals a capacity of 200GB.
You can see the difference between the classic magnetic layer and the AFC media in the pictures above. In the latter case, we have two magnetic layers with a thin layer of non-magnetic metal, ruthenium, in between. This RU layer magnetizes them with different polarity, thus creating so-called anti-ferromagnetic couples. The platter coating in Travelstar 80GB drives is called “Pixie Dust” and resembles a multilayer sandwich. It allows data density of 70Gbit per square inch.
Next, this Hitachi drive features fluid dynamic bearings that make the drive more robust to physical impacts and less noisy compared to motors with roller bearings.
The drive’s heads feature giant magneto-resistive effect (GMR). It accounts for a higher sensitivity to the magnetic fields of the platter, which in its turn helps to increase the capacity of the drive.
Partial Response Maximum Likelihood (PRML) technology helps to reach higher data transfer speeds, with fewer program errors per stored megabyte, and to filter the signal coming from the drive.
Enhanced Adaptive Battery Life Extender (ABLE) innovation helps to reduce the power consumption in the idle and standby modes. This is performed by means of dynamic selection of the optimal operational mode. Moreover, the disk’s response time is also reduced.
The heads load/unload technology, employed in the drive, is an alternative to the older Contact Start-Stop Technology – when the disk is stopped, the heads may land right on its surface to a physical contact. According to the new schematic, the heads are parked off the platter. Thus, the data density improves as well as robustness and power consumption.
The performance and reliability of products of the Travelstar 80GN line are upheld by such time-tested technologies as True Track Servo, Drive Fitness Test (DFT) and S.M.A.R.T.