* KOSPI rises, foreigners net sellers

* Korean won strengthens against dollar

* South Korea benchmark bond yield flat

SEOUL, Aug 22 (Reuters) - Round-up of South Korean financial markets:

** South Korean shares rose for a second day on Tuesday, tracking overnight gains in U.S. tech stocks, while investor focus was on monetary policy events due later this week. The Korean won firmed, while the benchmark bond yield was steady.

** The benchmark KOSPI was up 18.03 points, or 0.72%, at 2,526.83, as of 0136 GMT.

** "The index rose on dip-buying, with Nvidia's earnings and Jackson Hole likely to be next market movers," said Cho Jun-kee, an analyst at SK Securities.

** U.S.-listed shares of Nvidia jumped 8.5% overnight, providing supportive ground for local chipmakers, while the tech-heavy NASDAQ index jumped more than 1%.

** The Bank of Korea will leave its key policy rate unchanged at 3.50% for a fifth consecutive meeting on Thursday as inflation continues to ease and household debt remains high, according to a Reuters poll.

** Chipmaker Samsung Electronics rose 0.75% and peer SK Hynix gained 1.63%, while battery maker LG Energy Solution climbed 2.28%.

** Shares of Hyundai Motor added 0.59% and sister automaker Kia Corp gained 0.64%, while search engine Naver and instant messenger Kakao were up 3.96% and 1.65%, respectively.

** Most index heavyweights advanced, among 447 shares that rose of the total 930 traded issues.

** Foreigners were net sellers by a small margin of 7.9 billion won ($5.90 million) on the main board so far on Tuesday.

** The won was quoted at 1,339.6 per dollar on the onshore settlement platform, 0.22% higher than its previous close at 1,342.6.

** In money and debt markets, September futures on three-year treasury bonds fell 0.04 point to 103.28.

** The most liquid three-year Korean treasury bond yield rose 0.8 basis point to 3.807%, while the benchmark 10-year yield climbed 0.3 basis point to 3.980%.

($1 = 1,338.0600 won) (Reporting by Jihoon Lee)