NEW YORK (CNN/Money) - More gloomy news on the technology sector combined with cautiousness ahead of a key address by Federal Reserve Chairman Alan Greenspan before a Congressional panel could take stocks lower Wednesday.

Early Wednesday, Nasdaq and S&P futures pointed to some weakness at the open on Wall Street.

"There is a little bit of uncertainty about what exactly Mr. Greenspan will say today," said Khuram Chaudhry, equity strategist with Merrill Lynch in London. "Investors want to hear about interest rates. Yes, the economy has shown some signs of suffering recently, but that's countered by other data indicating continued improvement overall. Investors are cautious until they hear more from Greenspan today."

Greenspan testifies before the House Budget Committee beginning at 10:30 a.m. ET. He's expected to justify the Fed's current stance of gradually tightening interest rates as the economy gets stronger. He's also expected to discuss concerns about how the aging population threatens the Social Security system.

"Nothing for the time being suggests more than a moderate pace of rate hikes," said Tony Dwyer, equity market strategist with FTN Midwest Research. "There is a bit if nervousness out there. The other thing is that the market has had a good run and this is a normal pullback with a little bit of profit taking going on."

Meanwhile, Merrill Lynch on Wednesday raised a red flag on the wireless handset sector, saying that it is concerned about weaker wireless handset shipments in the September quarter and larger-than-expected inventory buildup.

The firm downgraded Motorola (MOT: Research, Estimates) to "neutral" from a "buy", saying that it anticipates increased margin pressure on newer models.

Oil prices slid early Wednesday. U.S. crude futures fell 39 cents to $42.92 a barrel in electronic trading, while Brent oil futures slipped 23 cents to $40.53 a barrel in London. World oil prices continued to ease as increased supplies from Organization of the Petroleum Exporting Countries (OPEC) weighed on market sentiment.

OPEC meets in Vienna on Sept. 15 to review output policy. Although prices are come down from the August highs, they are still up more than 30 percent from the beginning of the year.

The cartel's president Purnomo Yusgiantoro of Indonesia said prices were being inflated by political risk and estimated that world supplies now were in surplus over demand.

"What we see is the political premium between $10 and $15 per barrel," Purnomo was quoted as saying at the World Energy Congress in Sydney, Australia. "If you remove the non-fundamentals, then we hope the price will go down to a level of $30 per barrel.

The Dow Jones industrial average and Nasdaq composite index held on to 0.8 percent gains Tuesday as oil price pressure eased.

Asian-Pacific stocks ended mostly lower, with Tokyo's Nikkei index shaving 0.2 percent. European markets edged downward in morning activity. (Check the latest on world markets)

Treasury prices fell in early trading, sending the 10-year note yield up to 4.25 percent from 4.23 percent late Tuesday. The dollar advanced against the yen, but was weaker versus the euro. Gold was higher.

In other news, Piper Jaffery on Wednesday downgraded shares of business software maker Oracle (ORCL: Research, Estimates) to "market perform" from "market outperform."

Tech investors will also be keeping tabs on Texas Instruments (TXN: Research, Estimates), which is expected to deliver its mid-quarter update after the closing bell.

Time Warner (TWX: Research, Estimates), the parent of CNN/Money, is among the companies that have talked to the British Broadcasting Corp. about a possible acquisition of the BBC's Worldwide unit, which includes magazines and such television programs as "The Weakest Link."

Separately, pop singer Janet Jackson's bare breast flash earlier this year will result in a record $550,000 fine for 20 CBS television stations, according to a Reuters report Tuesday. The report said the FCC was unanimous in voting to fine the 20 stations owned by CBS, which is a unit of media conglomerate Viacom (VIA.B: Research, Estimates).  

-- from staff and wire reports