AMD is trying to track down and replace as many as 3,000 faulty Opteron processors that could produce "inconsistent results" under an unusual circumstance. The potential problem affects a number of single-core Opteron 152, 154, 252, 254, 852 and 854 processors manufactured in late 2005 or early 2006, AMD said Friday. The company hasn't seen the problem in production use, but has seen it in a test that combines high processor temperature, high outside temperature, and a large number of floating-point mathematical computations.

AMD is working with computer makers to track down the chips and is offering free replacements. The Sunnyvale, Calif.-based chipmaker has made PC processors for years, but only in 2003 entered the server market with the Opteron chip. Server chips typically offer higher performance, withstand higher heat, and have circuitry that lets several communicate in the same computer.