* Retail stocks higher on busiest day for internet shopping
* Western Digital, Micron Technology slip
* Oil falls on expectations of higher output
* Dow up 0.15 pct, S&P down 0.03 pct, Nasdaq down 0.16 pct (Updates to early afternoon)
By Sruthi Shankar and Rama Venkat Raman
Nov 27 (Reuters) - Wall Street's major indexes came off session highs in afternoon trading on Monday as a more than $1 slide in U.S. crude prices buffeted energy shares and semiconductor makers declined on concerns the memory chip "super cycle" would soon fade.
Oil majors Chevron fell about 1 percent, while Exxon dipped 0.4 percent.
Micron Technology declined 3 percent and Nvidia slipped 1.1 percent, with the Philadelphia semiconductor index on track to post its biggest percentage loss in more than two weeks.
The declines followed a 5 percent drop in shares of Samsung Electronics in Asian trading after Morgan Stanley downgraded the stock and argued that it was "time for a pause" on chipmakers, which have seen stellar performance this year.
The main indexes touched record intra-day highs earlier after retailers, including Amazon.com, rose on an expected surge in online sales on Cyber Monday, adding to strong sales on Black Friday.
Adobe Analytics said Cyber Monday is expected to drive $6.6 billion in internet sales this year, which would make it the largest U.S. online shopping day in history.
"Investors are looking at retail stocks as Black Friday and Cyber Monday have been a good start to the holiday season, and much stronger data on new home sales has lifted the market higher," said Kim Forrest, research analyst at Fort Pitt Capital Group in Pittsburgh.
Home Depot and Lowe's gained about 1 percent after data showed a surprise rise in sales of new U.S. single-family homes in October. Sales rose to their highest level in 10 years, according to the report.
At 12:33 p.m. ET (1733 GMT), the Dow Jones Industrial Average was up 35.13 points, or 0.15 percent, at 23,593.12, the S&P 500 was down 0.68 points, or 0.03 percent, at 2,601.74. The Nasdaq Composite was down 11.06 points, or 0.16 percent, at 6,878.11.
Stocks came under pressure after media reports that Japan received signals hinting that North Korea was preparing for a missile launch.
Two traders confirmed that the report weighed on the market.
Hard-disk maker Western Digital fell nearly 7 percent after Morgan Stanley downgraded the stock to "equal-weight", citing deteriorating prices for some products and uncertainty over a joint venture with Toshiba Memory .
Time Inc was up more than 9 percent after media company Meredith said it would buy the publisher of People, Sports Illustrated and Fortune magazines in a $1.84 billion deal. Meredith was up 11.7 percent.
Declining issues outnumbered advancers on the NYSE by 1,736 to 1,100. On the Nasdaq, 1,676 issues fell and 1,178 advanced.
Reporting by Sruthi Shankar in Bengaluru; Editing by Patrick Graham and Sriraj Kalluvila