Concerns about high-performance computers being used for military purposes in China and Russia have spurred the United States to tighten export rules for workstations and servers.
Early this month, the US Commerce Department issued rules that enable certain government departments to scrutinise the export of high-performance computers to the mainland and about 49 other countries. The rules apply to computers with speeds between 2,000 and 7,000 million theoretical operations per second (Mtops).
But some industry observers say the rules may be overly restrictive, because the low end of the range would apply to some machines commonly sold to corporations, not just supercomputers.
The rules implement a law passed last year tightening export procedures for high-powered computers destined for developing countries capable of building nuclear weapons. Those so-called Computer Tier 3 countries include China, Russia, Israel and India.
The rules were passed following reports China and Russia had diverted high-performance computers for military use. A Sun Microsystems supercomputer was returned to the US last September after the government discovered it was diverted illegally from a civilian research facility to a military and scientific institute in Changsha, Hunan province.
An industry source said there also had been investigations involving diverted equipment made by Silicon Graphics and its subsidiary, Cray Research.