(For a Reuters live blog on U.S., UK and European stock markets, click LIVE/ or type LIVE/ in a news window.) * Alphabet set for best day in nine months * Spotify drops as outlook disappoints * Amgen slips as earnings forecast falls short of estimates * Indexes: Dow down 0.17%, S&P up 0.10%, Nasdaq up 0.10% (Adds comment, details; updates prices) Feb 3 (Reuters) - The S&P 500 and the Nasdaq treaded water in choppy trading on Wednesday after two days of sharp gains while Alphabet Inc’s shares headed for their best day in nine months following its strong quarterly results. Alphabet jumped 7.3% as it benefited from lockdowns that drove retail and other advertisers online. The Google owner’s shares pushed the communication services index 2.1% higher to an all-time high. Five of the 11 major S&P sectors were in the positive territory, including economy-linked energy, financials and materials . Amazon.com Inc dipped 0.4% as Jeff Bezos’ surprise move to step down as chief executive quashed optimism about bumper quarterly results. However, analysts were upbeat on the promotion of its cloud computing head to the top job. About 83% of reports from S&P 500 companies so far have surpassed analysts’ earnings expectations, with 97% of results from technology companies beating estimates, according to IBES data from Refinitiv. The S&P 500 has climbed about 3% in the past two sessions as investors monitored talks over the next round of fiscal stimulus following a bout of market volatility last week due to a retail trading frenzy. “The market really just needs to take a breather before resuming the uptrend ... investors are getting a handle over what the stimulus is going to look like moving forward,” said Thomas Hayes, managing member at Great Hill Capital LLC in New York. U.S. President Joe Biden on Wednesday will meet congressional Democrats preparing to advance his $1.9 trillion COVID-19 relief plan despite Republican pushback. Videogame retailer GameStop Corp rose about 3%, clawing back some gains after nearly halving in value on Tuesday on the back of a social media-driven trading rollercoaster ride. U.S. Treasury Secretary Janet Yellen is calling a meeting of top officials, including from the Securities and Exchange Commission and the Federal Reserve, this week to discuss market volatility. At 11:25 a.m. ET, the S&P 500 gained 3.90 points, or 0.10%, to 3,830.21 and the Nasdaq Composite gained 13.60 points, or 0.10%, to 13,626.37. The Dow Jones Industrial Average fell 0.17%, weighed down by a 3.3% fall in shares of Amgen Inc after the U.S. biotech forecast 2021 earnings below estimates and said it had paused or halted enrollment for clinical trials of three cancer drugs. On the economic front, the ADP Report showed hiring by U.S. private employers rebounded by 174,000 in January after a drop in December. A more comprehensive jobs report is expected on Friday. A separate ISM survey showed U.S. services industry activity raced to its highest level in nearly two years in January. Advancing issues outnumbered decliners by a 1.1-to-1 ratio on the NYSE and by a 1.1-to-1 ratio on the Nasdaq. The S&P 500 posted seven new 52-week highs and no new lows while the Nasdaq recorded 186 new highs and five new lows. (Reporting by Devik Jain and Medha Singh in Bengaluru; Editing by Maju Samuel)