The company's redesigned Opteron processor is the first from AMD to feature four computing engines on a single chip instead of just one or two.
AMD's belated entry into the "quad-core" market is a critical element in the financially strapped company's offensive against Intel Corp., the world's largest semiconductor company, whose market value of $148 billion makes it 21 times bigger than AMD.
Intel has outspent its smaller rival on new technologies and better absorbed the pain of a brutal price battle that has led to embarrassing market-share losses AMD hopes its new chip will reverse.
Also Monday, Intel raised its third-quarter revenue outlook on stronger-than expected demand for its microprocessors. The company now expects revenue between $9.4 billion and $9.8 billion, up from its previous range of $9 billion to $9.6 billion.