iSuppli's "pessimistic outlook" for HDD shipments estimates that as few as 149.4 million units will go out during the current quarter, a 10% sequential drop. 's more optimistic outlook calls for global HDD shipments of 157.5 million units in the quarter ending Dec. 31, basically flat compared to the 158.3 million units shipped in the third quarter. If that forecast holds true, overall HDD shipments for 2008 would total 593.2 million units, up 14.9% compared to the 516.2 million units shipped in 2007, iSuppli said.

Krishna Chander, senior analyst for storage systems at iSuppli, said her company considers the optimistic sales forecast more accurate because it is in line with sales predictions from leading HDD makers, such as and (WDC). Seagate in October predicted the HDD industry would ship 156 million units in the fourth quarter; WDC's outlook, when extrapolated, amounts to about 161.7 million.

"OEMs that traditionally purchase more components in the fourth quarter are reducing their procurement budgets, or are buying with low incoming inventory -- resulting in reduced pricing for HDDs," Chander said.

In September, iSuppli forecast HDD shipments would rise 4.9% sequentially in the fourth quarter and 16.6% for all of 2008. Next year will bring even greater uncertainty, according to iSuppli. HDD unit sales growth is predicted to range from 4.3% to 6.8% above 2008 levels.

The average selling price of an HDD is also expected to drop sharply next year, iSuppli stated. HDD's are expected to sell for about US$58 in the second quarter of 2009 before recovering to the near $60 range late in the fourth quarter. Those prices reflect an average of all HDDs regardless of size. "This weak pricing represents a drag on the HDD industry as a whole, one that will make it harder to cut a profit," iSuppli stated.