[Sticky] GPU Performance and Clarification
But the HD5970 is dual chip isn't it?
Today, AMD is executing the third part of its four-phase Radeon HD 5000 series launch today with the release of the Radeon HD 5970. The Radeon HD 5970 is codenamed Hemlock and is not a completely new GPU. Instead, it's a pair of Cypress GPUs connected together with a PCI Express 2.0 bridge chip to deliver enough performance to shatter every record in the book.
Source - Bit-Tech