Any vendor or user who wants to ship a server into the European Union past the end of June will have to comply with the European directive RoHS, or restriction of the use of certain hazardous substances in electrical and electronic equipment. The law will bar the import of PCs, servers and other electronic equipment that includes six hazardous materials, including lead, mercury and cadmium. There is an exception for lead in servers, for now at least, because of some concerns about its impact on performance. Lead is commonly used in solder.

"One thing we have achieved with this System x release is the RoHS compliance ... and because we need to do that by June 30 to sell within the European Union, [that] is why we are introducing a turn of the products at this point in time," said Jay Bretzman, director of high-performance systems at IBM.

IBM said it will release RoHS versions of its other products in time to meet the deadline -- even if they haven't yet been rebranded as System x hardware. Systems that don't meet the RoHS requirements but are already in the EU can still be sold after July 1.

The European law will have ramifications for users in the U.S., who will also be getting hardware free of these hazardous materials. "It will become the default," said Krista Botsford, managing partner at 5-Trees LLC, a Burlington, Mass., firm that advises vendors on environmental compliance issues. "Most manufacturers do not want to run two separate assembly lines."

The new System x systems don't make the eServer products IBM is selling today obsolete. "It's the same-generation technology," said Bretzman. Other servers in the xSeries line will be renamed when they get chip upgrades on a schedule that will take months, said Bretzman. IBM said all of its eSeries servers will meet the coming EU directive.