SANTA CLARA, Calif. — The big chip-maker Intel Corp. is cutting its sales forecast for the current quarter, adding fresh evidence that a rickety economy is putting a damper on the back-to-school shopping season.

Intel is the world’s biggest provider of microprocessors for PCs and a bellwether for the broader technology industry.

In a statement Friday, the company said it is seeing “weaker than expected demand for consumer PCs in mature markets.”

The company says it now expects revenue of $10.8 billion to $11.2 billion for the fiscal third quarter, which ends in September. That compares with a previous forecast of $11.2 billion to $12 billion.

On average, analysts surveyed by Thomson Reuters expected $11.5 billion.

Intel shares slipped a penny in morning trading Friday to $18.17.

Last week, PC makers Dell Inc. and Hewlett-Packard Co. also raised red flags about what is normally a robust season for sales. Dell Chief Financial Officer Brian Gladden said in a conference call that the back-to-school shopping season has been “a little weaker than we would have expected.”

Todd Bradley, head of HP’s PC division, told investors the company saw some “softness” in the consumer laptop market and that back-to-school shopping started “somewhat late for us.”