"In Western Europe, EMC had the largest revenues for external arrays for the first time in 2004," said Eric Sheppard, research manager at IDC in Europe. EMC had sales of $246.9m (£129.1m), overtaking HP’s $243.5m and seizing the first place in external storage -- a prize HP took when it merged with Compaq in 2001.
HP has faced growing competition on several fronts -- last year, it also lost the leadership in PCs to Dell.
HP responded to EMC's success by claiming the lead in total storage systems. HP sold $451.8m storage systems, including internal units shipped with servers -- a market where EMC does not compete.
However, the external figure looks like being more significant. External storage is already the largest part of the market, and is becoming more important as the price differential for external units disappears.
"For the whole year, $4bn of the $6.6bn storage market in Western Europe was for external units. More and more of the market is becoming external as blades push it in that direction," said Sheppard.
Over the whole year, the internal storage market actually went down by 1.4 percent -- though capacities continued growing. External storage went up by 5.2 percent in Western Europe, said Sheppard.
Customers are buying external storage because it fits well with modular systems such as blades; it is also becoming relatively cheaper, even compared with the falling costs in the whole storage market: "In 2001, External storage sold at 1.8 times the price of internal storage. In 2004, that premium had fallen to 1.2," Sheppard reported.