Previously, Gartner vice president Andrew Butler warned dual-core processors could increase software licensing costs by up to 50 percent. "All four ... happening at the same time is a recipe for software pricing mayhem," Butler said, before urging enterprises to protect themselves by initiating contract negotiations immediately.

Gartner also predicted software licensing "by core" could double price relative to performance.

"If a new, dual-core design offers only a 50 percent improvement, a doubling in the licence fee becomes a tax on technology innovation with little return," Butler said. Vendors contend they will remain flexible on per-processor pricing.

Microsoft Australia's server business group director, Tony Ward, said users must ask if the performance of dual-core processors is equivalent to two physical processors. "If you do get the same performance it doesn't matter," he said.