Tech stocks continued to erode Wednesday morning, while the broader market wobbled, as investors were cautious ahead of an onslaught of second-quarter earnings reports.

The Nasdaq composite (Charts) lost 0.3 percent in the early going. The Dow Jones Industrial average (Charts) and the broader Standard & Poor's 500 (Charts) index both saw smaller declines.

Stocks had managed to stage a late-session comeback Tuesday, after improved profit guidance from chipmaker KLA-Tencor brought out the bulls, following a tough morning.

However, the tone was mixed again Wednesday, with investors keeping an eye on quarterly earnings. A few companies have reported their second-quarter results, but the period of confessionals doesn't really heat up until later in the month.

Late Tuesday, drug developer Genentech (up $0.00 to $84.06, Charts) reported quarterly earnings that rose from a year ago and beat estimates thanks to strong sales of its colon cancer treatment Avastin. However, analysts were expecting even stronger sales of the drug, and the stock slipped Wednesday morning.

In other corporate news, Microsoft (up $0.00 to $23.10, Charts) was fined $357 million by European regulators for failing to abide by a previous antitrust ruling pertaining to its windows operating system. Shares dipped 1 percent in the early going.

U.S. light crude oil for August delivery rose 26 cents to $74.42 a barrel on in electronic trading ahead of the weekly oil inventories report, due out at around 10:30 a.m. ET.

COMEX gold for August delivery added $8.40 to $651.50 an ounce.

Treasury prices slipped, raising the yield on the benchmark 10-year note to 5.14 percent from 5.08 percent late Tuesday. Bond prices and yields move in opposite directions.

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