Advanced Micro Devices ( AMD) slashed second-quarter revenue guidance, citing lower sales of processors for desktop computers and some mobile devices. The chipmaker expects second-quarter revenue of $1.22 billion, up 52% from a year ago but down 9% from the first quarter. AMD had previously forecast second-quarter sales that were equal to or down slightly from the first quarter. Analysts were expecting sales of $1.31 billion, according to Thomson First Call. "Record AMD Opteron processor sales were driven by continued strong demand for single-, dual- and multi-socket configurations for servers and workstations," the company said. "Sales of entry-level and mainstream mobile and desktop processors were down." AMD's sales shortfall comes during a quarter in which Intel ( INTC) cut prices on many of its microprocessor offerings in an effort to fend of its rival's market-share encroachment. Shares of AMD closed Thursday at $23.83. In premarket trading Friday, the stock fell $1.12, or 4.7%, to $22.71.