Tokyo stocks opened lower Thursday, as high tech issues led declines after eagerly awaited earnings results of U.S. chip giant Nvidia Corp. failed to impress investors. In the first 15 minutes of trading, the 225-issue Nikkei Stock Average fell 271.01 points, or 0.71 percent, from Wednesday to 38,100.75. The broader Topix index was down 4.22 points, or 0.16 percent, at 2,687.90. On the top-tier Prime Market, decliners were led by electric appliance, nonferrous metal and machinery issues. At 9 a.m., the dollar fetched 144.44-45 yen compared with 144.53-63 yen in New York and 144.55-58 yen in To…