Shares of Advanced Micro Devices Inc. shot up 5.6% in very active trading Tuesday morning, putting them on track for their first gain in six days amid a broad rally in chip stocks. Volume of 37.4 million shares made AMD's stock the most actively traded on major U.S. exchanges. The stock had tumbled 12% over a five-session losing streak through Monday. AMD's rally comes as the PHLX Semiconductor Index climbed 4.6%, with all 30 components gaining ground, led by the 6.5% jump in Micron Technology Inc. shares. Meanwhile, chipmaker Intel Corp.'s stock rallied 3.7% to pace the Dow Jones Industrial Average's gainers.