Seagate 7200.10 750GB Hard Drive

INTRODUCTION

Within the last two months we have published two reviews on two separate models of Seagate's hard drives that were each 500 Gb in capacity: the 7200.9 and the NL-35. With each review we stipulated that capacities of these drives were growing at an incredibly rapid rate to contend with the consumer's need for more data storage. In the back of our minds, although not publicly stated, we felt that a pinnacle had been reached at the 500 Gb level that would take a while to surpass. Little did we know that just around the corner was an even newer and more expansive technology waiting to meet our storage needs. So much for supposition on our parts!

Common sense would seem to indicate that there has to be a limitation to the number of platters that can be placed in these drives while still maintaining the 3.5 inch form factor that is used in the vast majority of all of today's desktop computers and servers. Did Seagate sprinkle a magic dust onto the surface of these platters to make them hold more data? While somewhat of a joke this question has some semblance of accuracy that will be discussed later in this review.

What is even more amazing than the seemingly endless increase in capacities is that each new drive iteration to date has been quantitatively faster than its predecessor. How the speed of these drives has continued to proportionately rise while still keeping the same 7200 RPM rating is also somewhat of a mystery. One answer might be that the cache size has continued to grow from 2Mb to 8Mb, and now to 16Mb. Is this the answer? We'll also discuss this aspect of drive architecture later in this review.

Enough of the "SWAGS" (Scientific Wild Ass Guesses); it's time for some facts! Join Scott and I while we examine and hopefully discover the intricacies of Seagate's latest and potentially greatest drive to date: the Barracuda 7200.10, 750 gigabyte hard drive.

FUNCTIONALITY & SPECIFICATIONS

Before looking at the drive specs we thought it appropriate to do some research and answer some of the questions initiated in the Introduction. We learned many of the answers to many of our questions by perusing technical papers supplied by Seagate.

First, and foremost, how did Seagate increase the volume of their drives so radically? To answer that question we must first understand areal density. To paraphrase Webopedia's definition: Areal Density also called bit density is the amount of data that can be packed onto a storage medium. Areal densities are generally measured in gigabits per square inch. The term is useful for comparing different types of media, such as magnetic disks and optical disks. Current magnetic and optical disks have areal densities of several gigabits per square inch.

Next we turned to Seagate for their technical comments on areal density:   "To increase areal densities in longitudinal recording and boost overall storage capacity, the data bits must be shrunk and packed more closely together. However, if the bit becomes too small, the magnetic energy holding the bit in place may also become so small that thermal energy can cause it to demagnetize, a phenomenon known as superparamagnetism. To avoid superparamagnetism, disc media manufacturers have been increasing the coercivity (the field required to write a bit) of the media. However, the fields that can be applied are limited by the magnetic materials making up the write head."