The Sunnyvale, California-based company said revenue for the fourth quarter ending December 26, 2004 is expected to be up slightly from $1.24 billion in the third quarter, but operating income will be down significantly from third-quarter operating income of $68.4 million.

In a competitive and challenging NOR flash memory market, the Memory Group is anticipated to have lower fourth-quarter sales and an operating loss, the company said in a statement. In a previous forecast, AMD said it expected memory sales to be either flat or up during the quarter.

NOR is a type of flash memory that retains data when the device powered down and is widely used in mobile phones. It is likely that AMD’s downward guidance means that its rival Intel Corp has gained ground in the flash memory market and applied significant pricing pressure.

However, the good news for AMD is that processor side revenue remains healthy, and is likely to be higher than the third quarter. It should also report a profit. AMD is scheduled to report its fourth-quarter results on January 18.