* FTSEurofirst 300 falls 0.4 percent, hits one-week low
* Euro STOXX 50 down 0.5 percent, but bullish 'golden cross'
* Resource-related stocks hit as QE doubts boost dollar
* SAP, Michelin, Heineken drop as results fail to impress
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By Blaise Robinson
PARIS, Oct 27 (Reuters) - European stocks fell in early trade on Wednesday, as mounting doubts about how aggressive the Federal Reserve will be in pumping more money into the system rattled investors and boosted the dollar.
But the retreat was limited as the Euro STOXX 50, the euro zone's blue-chip index, ran into a strong support level and sent a bullish signal as the index's 50-day moving average crossed above its 200-day moving average, known as a golden cross.
That upward momentum indicator last occurred in June 2009, and the benchmark index climbed more than 20 percent in the following four months.
At 0835 GMT, the FTSEurofirst 300 index of top European shares was down 0.4 percent at 1,085.70 points. The Euro STOXX 50 fell 0.5 percent to 2,841.30 points, after testing a key support level at 2,837.89, which represents the 38.2 percent Fibonacci retracement of the index's fall from a 2007 high to a 2009 low.
"Although we might get a small pullback in the short term, indexes have clearly entered into a bullish phase by breaking out above the summer range, with the DAX recently hitting its highest of the year," said Vincent Ganne, technical analyst at IG Markets, in Paris. The Wall Street Journal reported on Wednesday that the Fed is likely next week to unveil a programme of U.S. Treasury bond purchases worth a few hundred billion dollars over several months. In a Reuters survey earlier this month, U.S. primary dealers' projections for the size of the Fed's expected quantitative easing had ranged from $500 billion to $1.5 trillion.
"If the next round of quantitative easing is indeed lower than what people have been expected, it's going to be negative for equities, at least for U.S. stocks, so we could take a breather after the recent rally," said Pierre-Yves Gauthier, head of research at Alphavalue in Paris.
"But the downside risk is limited by the fact that stock valuation levels are attractive and companies have been releasing strong figures overall. The further we get into the earnings season in Europe, the less people will focus on the dollar swings."
Mining shares dropped along with metal prices, hit by the dollar's rise, with both Xstrata and Rio Tinto down 2.1 percent.
German business software maker SAP fell 3.4 percent as investors booked recent strong gains after the company's results and outlook failed to impress.
French tyre maker Michelin dropped 1.9 percent as worries over raw material costs for 2011 eclipsed good quarterly results.
Heineken NV tumbled 3.7 percent as the world's third-largest brewer reported weaker-than-expected third-quarter sales.
Bucking the trend, Nordea rose 3.3 percent after the biggest Nordic bank by value posted third-quarter earnings above all forecasts, and Deutsche Bank AG gained 2 percent after reporting resilient profit from investment banking in the third quarter.
(Reporting by Blaise Robinson; Editing by Erica Billingham)