Tech stocks continued their downward slide on Thursday along with the rest of the major indices, with no end in sight to the market volatility. The Nasdaq shed 57 points, or 3.4%, to 1625 in recent trading. Shares of Advanced Micro Devices ( AMD) were tumbling on Thursday despite the chipmaker's announcement a day earlier to slash 500 jobs, or 3% of its workforce, in an effort to return it to profitability. That was not enough to appease investors, who drove down the stock by 11.6% to $3.14. Shares of Amazon ( AMZN) slipped 6.6% to $48.53 after Citigroup downgraded it to hold from buy. Despite a recent surge in Amazon's stock price following third-quarter results that showed still strong growth rates, Citigroup noted that consumer spending trends at other ecommerce companies like Expedia ( EXPE) and Blue Nile ( NILE) indicate ongoing weakness. Shares of Activision Blizzard ( ATVI) jumped 11% to $12.19 one day after the company edged past Wall Street estimates for its third-quarter results. The video game publisher posted a loss of $108 million, or 8 cents a share, down from a profit of $48 million, or 8 cents a share, a year ago. Excluding items related to the July merger with Vivendi's Blizzard unit, as well stock-options expenses, Activision said it earned a profit of 7 cents a share in the quarter. That was well above analysts' expectations of 4 cents a share. Third-quarter revenue more than doubled from a year ago to $711 million, beating Wall Street estimates of $632 million, according to Thomson Reuters.