Advanced Micro Devices announced yesterday that it has replaced CTO Fred Weber with Ex-IBM PC division CTO Phil Hester. Hester most recently worked with server computer manufacturer Newisys, which used AMD"s Opteron server class processors in its systems. According to AMD, Weber left the company to "explore new opportunities" with early-stage technology ventures. As CTO, Hester will oversee the development of AMD"s next generation microprocessor designs.