Fueled by demand in the Asia/Pacific region and Japan, external disk storage systems revenues grew 8% YTY to $3.5 bln in Q2 of 2004, according to IDC. IDC defines a disk storage system as a set of controllers, cables, and host bus adapters associated with three or more disks. The analyst said total disk storage systems market grew 5%. Vendors shipped 275 petabytes of storage in Q2 2004. HP maintained its lead in total disk storage systems, including internal and external storage, with 23% of the market. IBM is No. 2 with 20.3% and EMC follows with 14.4%. EMC led the external disk storage systems market with a 20.7% revenue share, good for a 19.5% YTY revenue growth for Q2. HP came in a solid second with 18.2%, but the company's revenue was down 8.3% YTY after suffering a 15% decline in storage systems sales. IBM held the No. 3 slot with 13.5%.