According to the Wall Street Journal, two Goldman Sachs hedge funds are having trouble. The first of these revelations on Thursday seemed to trigger an acceleration of the market slide that began in Europe.

Apparently, the computer models that had proved so successful over the last few years caused large trading losses in the last three weeks.

Unfortunately, WSJ's stories are not open to non-subscribers.

Blind to Trend, 'Quant' Funds Pay Heavy Price

Computers don't always work.

That was the lesson so far this month for many so-called quant hedge funds, whose trading is dictated by complex computer programs.

The markets' volatility of the past few weeks has taken a toll on many widely known funds for sophisticated investors, notably a once-highflying hedge fund at Wall Street's Goldman Sachs Group Inc.

Global Alpha, Goldman's widely known internal hedge fund, is now down about 16% for the year after a choppy July, when its performance fell about 8%, according to people briefed on the matter.

Second Goldman Hedge Fund Moves to Sell Some Positions

A second Goldman Sachs Group Inc. hedge fund has hit a rocky patch and has sold down some of its positions, according to a person familiar with the matter.

Goldman's North American Equity Opportunities hedge fund had $767 million under management earlier this year. The Fund was down over 15% this year, through July 27, according to investors and was down more than 11% in July alone. It is not known how much the fund has sold in recent days.

Just before the close yesterday (Wednesday), Goldman Sachs denied rumors that it was about to announce problems with one or more quantitative hedge funds. The Dow, which had tanked about a hundred points in a few minutes on the rumor, rebounded about a hundred points on the denial issued about 10 minutes before Wednesday's close.