Today Western Digital announced that it has achieved 520 Gb/in2 areal density in an actual demonstration using its own perpendicular magnetic recording (PMR)/tunneling magneto-resistive (TuMR) head technology. For those of you who are counting, that makes it the highest density ever reached using continuous media. A density of this magnitude produces a 3.5-inch hard drive storing 640 GB-per-platter and single hard drive capacities as large as 3 TB. Compare that to the current leading density of around 200 Gb/in2 being shipped high volume products like WD's 250 GB Scorpio(R) 2.5-inch drive. That's all well and good, but it looks like you will have to wait to get your hands on this technology. Current estimates put the release at around 2010.

WD(R) Demonstrates Highest Hard Drive Density Company Achieves 520 Gb/in2 Areal Density in Demonstration; Result of Ongoing Technology Investments TOKYO and FREMONT, Calif., Oct. 17 /PRNewswire-FirstCall/ — Western Digital Corp. (NYSE: WDC) today announced that it has achieved 520 Gb/in2 areal density — the hard drive industry's highest demonstrated density to date using continuous media. The company revealed the milestone this week at the Perpendicular Magnetic Recording Conference in Tokyo after an earlier demonstration in California . Following WD's growing investments in technology the past five years, the company achieved 520 Gb/in2 using its own perpendicular magnetic recording (PMR)/tunneling magneto-resistive (TuMR) head technology. This level of density produces a 3.5-inch hard drive storing 640 GB-per-platter and single hard drive capacities as large as 3 TB. Based on the industry's current density growth rate of more than 40 percent per year, those capacities are expected to be available in the 2010 timeframe. Current industry-leading hard drive densities shipping in high volume are about 200 Gb/in2, as featured in WD's 250 GB WD Scorpio(R) 2.5-inch drive for notebooks and mobile applications, which began shipping in May 2007. "WD was the first hard drive manufacturer to ship in volume the 250 GB capacity point in the 2.5-inch form factor," said Hossein Moghadam, chief technology officer for WD. "Our technology investments position WD with our customers as a leading choice for the highest, cutting-edge capacities. Our top priority will be to remain keenly focused on providing the highest quality and reliability, which customers have come to expect from WD after years of relying on our products." WD demonstrated 520 Gb/in2 density in its Magnetic Head Operation labs in Fremont, Calif., earlier this month. Moghadam added, "The milestone was realized using our current-technology MgO reader, illustrating the extendibility of PMR-TuMR head technology generations into the future." About WD WD, one of the storage industry's pioneers and long-time leaders, provides products and services for people and organizations that collect, manage and use digital information. The company produces reliable, high-performance hard drives that keep users' data accessible and secure from loss. WD applies its storage expertise to consumer products for external, portable and shared storage applications.

WD was founded in 1970. The company's storage products are marketed to leading systems manufacturers, selected resellers andretailers under the Western Digital and WD brand names. Visit the Investor section of the company's Web site (http://www.westerndigital.com) to access a variety of financial and investor information.

This press release contains forward-looking statements, including statements relating to density growth rates, dates certain capacities are expected to be available based on those growth rates and the extendibility of PMR-TuMR head technology generations into the future. These forward-looking statements are based on current management expectations, and actual results may differ materially as a result of several factors, including: technical and manufacturing challenges related to changes in areal density; changes in technology; business conditions generally; and other risks and uncertainties listed in WD's recent SEC filings, including its form 10-K for fiscal 2007. WD undertakes no obligation to update these forward-looking statements to reflect new information or events or for any other reason.

Western Digital, WD and the WD logo are registered trademarks of Western Digital Technologies, Inc. All other trademarks herein are property of their respective owner. One gigabyte (GB) = 1 billion bytes. Total accessible capacity varies depending on operating environment.