Sonnet Technologies today announced a new line of dual processor upgrade cards — the Encore/MDX G4 Duet 1.6 GHz (US$499.95) and 1.8 GHz ($599.95) — the first high-speed processor cards for Apple’s popular Power Mac G4 MDD (Mirrored Drive Door) and Xserve G4. The Encore/MDX G4 Duet comes complete for installation into either tower or server. The original MDDs and G4 XServes were shipped in 2003 and 2004 in single and dual CPU configurations starting at 867 MHz and 1GHz, respectively. Encore/MDX G4 Duet upgrades are based on the Freescale Semiconductor (formerly a division of Motorola) PowerPC G4 7447A processors, featuring 512K of SRAM on-chip L2 cache per processor. Each upgrade includes a factory-attached heat sink, fan, and mounting bracket for either MDD or Xserve installation.