Other World Computing (OWC) today announced a new Mercury Extreme G4/1.25 Gigahertz (GHz) processor upgrade that the company says is guaranteed to run at actual clock speeds of up to 1.467GHz. This addition to the line of AGP processor upgrades replaces OWC’s prior 1.25-1.26GHz Mercury Extreme model, and uses Motorola’s new PowerPC G4 7455B 1.25GHz processor. It is immediately available online from OWC for US$429.99. OWC Mercury Extreme G4 processor upgrades are backed by a three-year warranty and a 30-day 100 percent money-back guarantee.