SEOUL, Sept. 10 (Yonhap) -- South Korean stocks opened higher on Wednesday, driven by big-cap tech shares, as investor sentiment was boosted by overnight gains on Wall Street amid expectations of the Federal Reserve's interest rate cut.

The benchmark Korea Composite Stock Price Index (KOSPI) added 28.16 points, or 0.86 percent, to 3,288.21 in the first 15 minutes of trading.

Offshore investors were net buyers of local shares, effectively offsetting selling by individual investors.

Overnight, U.S. stocks gathered ground as weak jobs data bolstered bets that the Fed would cut interest rates at its policy meeting next week. The Dow Jones Industrial Average rose 0.43 percent, and the tech-heavy Nasdaq composite gained 0.37 percent. The S&P 500 index went up 0.27 percent.

In Seoul, chip shares got off to a strong start.

Market bellwether Samsung Electronics increased 0.84 percent, and chip giant SK hynix surged 3.3 percent.

But leading battery maker LG Energy Solution tumbled 1.87 percent, and major chemical firm LG Chem lost 1.79 percent on profit-taking.

Defense giant Hanwha Aerospace surged 2.54 percent, and nuclear power plant manufacturer Doosan Enerbility advanced 0.8 percent.

Automakers opened higher. Top automaker Hyundai Motor and its sister affiliate Kia added 0.57 percent.

Leading shipbuilder HD Hyundai Heavy gained 0.4 percent, and its rival Hanwha Ocean went up 0.18 percent.

Bio shares opened mixed. Leading bio company Samsung Biologics shed 0.1 percent, and Celltrion edged down 0.06 percent.

No. 1 financial firm KB Financial Group jumped 1.82 percent, while major steelmaker POSCO Holdings shed 0.18 percent.

The local currency was trading at 1,390.15 won against the greenback at 9:15 a.m., down 2.25 won from the previous session.