UPDATE 1-MEMC Electronics cuts Q4 outlook

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Nov 17 (Reuters) - Silicon wafers maker MEMC Electronic Materials Inc (WFR.N) cut its fourth-quarter revenue outlook, citing weak semiconductor and solar markets.

The company now expects revenue of about $500 million, compared with its earlier estimate of $540 million to $600 million.

MEMC, whose customers include South Korea's Samsung (005930.KS) and China's Yingli Green Energy (YGE.N), cut its gross margin outlook by 2 percent to about 48 percent.

However, the supplier of wafers to the chip and solar industries, expects operating expenses to be about $27 million, down from its previous estimate of $41 million, helped by a fall in stock option expense related to the resignation of its former chief executive.

The company's former chief executive Nabeel Gareeb, who played a key role in transforming the semiconductor firm to both a silicon and solar-wafers company, resigned in October.

Shares of the company closed down 13 percent at $13.39 Monday on the New York Stock Exchange. (Reporting by Anurag Kotoky in Bangalore; Editing by Anil D'Silva)