US STOCKS-Wall St flat, eyes German court hearing on euro bailout

* Spanish yields ease on German court hopes

* Alcoa tops estimate to begin earnings season

* Applied Materials adjusts outlook, shares drop

* AMD drops after warning

* Indexes up: Dow 0.5 pct, S&P 0.5 pct, Nasdaq 0.5 pct

By Chuck Mikolajczak

NEW YORK, July 10 (Reuters) - U.S. stocks were flat on Tuesday, as optimism Germany's top court will approve the euro zone's new bailout fund was offset by weakness in the U.S. technology sector after several profit warnings.

Trade was choppy as it has been recently on some of the lightest volume sessions this year, as the S&P 500 followed up its best three-day run since December with three straight declines.

Investors were in hopes that the German Constitutional Court will quickly approve Europe's new bailout plan and budget rules, after German Finance Minister Wolfgang Schaeuble warned the court any significant delay could rattle markets.

"Everyone is going to sit and wait because potentially (the court) could say it doesn't work," said Ken Polcari, Managing Director, ICAP Equities in New York.

"It's baby steps - it is going in the right direction but at any moment it could be derailed, that is why you have the lack of commitment."

Bank stocks, highly sensitive to developments in the euro zone, were among the best performers. JPMorgan Chase & Co rose 1.3 percent to $34.39 and U.S. Bancorp gained 1.5 percent to $32.52. The KBW Bank index advanced 1.1 percent.

Spanish bond yields backed off the 7 percent level, which has forced other countries to seek a bailout, on hopes the plan will be approved.

The FTSEurofirst 300 index was up 1.3 percent in a broad rally, putting the index on track for its first gain in the past five sessions. An index of European bank shares gained 1.6 percent.

The Dow Jones industrial average gained 63.43 points, or 0.50 percent, to 12,799.72. The Standard & Poor's 500 Index rose 6.44 points, or 0.48 percent, to 1,358.90. The Nasdaq Composite Index advanced 15.14 points, or 0.52 percent, to 2,946.91.

Advanced Micro Devices tumbled 7.8 percent to $5.18 after the chipmaker slashed its outlook for second-quarter revenue after seeing disappointing sales in China and Europe.

Applied Materials Inc lost 1 percent to $10.90 after the chip-gear maker said it expects to miss its full-year estimates and its third-quarter results will be at the low-end of its previous outlook. The PHLX semiconductor index shed 0.1 percent.

Alcoa Inc late on Monday kicked off quarterly earnings season with revenue and profit that beat Wall Street's expectations even though prices for its aluminum are at nearly two-year lows, and it forecast growing demand in the aerospace and auto sectors. Shares of the aluminum giant lost 1.4 percent to $8.64.

Intel Corp will spend more than $4 billion on up to 15 percent of ASML and bankroll the Dutch company's research into costly next-generation chipmaking technology, a major vote of confidence in the European firm. U.S.-listed shares of ASML jumped 9.2 percent to $52.92 and Intel gained 0.8 percent to $26.37.

Mako Surgical Corp plunged 38.9 percent to $15.04 after the company posted lower-than-expected sales of its surgical robot for the second quarter in a row and cut its sales forecast for the full year after the close on Monday.