(updates to midday)
* HSI up 0.2 pct, H-shares index up 0.2 pct
* HSBC up up 2.2 pct, contributes third of HSI gain
* CNOOC down 1.3 pct, top drag as oil prices dip
* Lenovo up 0.9 pct, shrugs off HP shares slide
By Vikram Subhedar
HONG KONG, Oct 4 (Reuters) - Hong Kong shares rose slightly on Thursday as financials, led by index heavyweight HSBC , helped offset weakness in oil producers hurt by lower oil prices.
The Hang Seng index was up 0.2 percent at 20,929.3 by the midday trading break. The China Enterprises index of top locally listed mainland firms also rose 0.2 percent.
With China's domestic markets shut through the week, trading activity on the Hong Kong stock exchange was sluggish, as investors remained concerned about the impact of the global trade slowdown on China.
"The unfortunate thing is that we haven't really seen the bottom yet as far as Chinese economic growth is concerned," said Raymond Chan, chief investment officer at Allianz Global Investors, Asia-Pacific.
"Markets want to see some stabilization," said Chan, suggesting investors steer clear of companies reliant on exports and focus instead on businesses that can generate cash and benefit from Chinese consumer spending.
Hong Kong retail sales data, expected after the close of market hours, will be closely watched for signs of mainland tourist spending during the Chinese holiday week.
CNOOC shares fell 1.3 percent and were the top drags on the Hang Seng. Sinopec Corp was down 0.8 percent.
Worries over weak demand for oil have pushed Brent futures down more than 7 percent since their September highs, dragging down shares of China's top producers.
Helping to counter those losses, HSBC Holdings advanced 2.2 percent after the bank, Europe's largest lender, said its core tier 1 ratio was above the levels required by the European Banking Authority (EBA).
HSBC said its core tier 1 ratio as of 30 June 2012 was 11.3 percent compared with the 9 percent level published by the EBA in its December 2011 recommendation.
Shares of insurer AIA Group rose 0.5 percent, hovering near record highs. AIA is seen as the frontrunner to buy some of ING's Southeast Asian operations and as several other global insurers are stepping up their presence in the region to tap rapid growth in insurance premiums.
Lenovo Group shrugged off weakness in PC-related shares across Asia after Hewlett-Packard shares slumped to a nine-year low on a bleak forecast for its turnaround.
Lenovo, which may overtake HP as the world's biggest PC seller this year, rose 0.9 percent, reversing a 2 percent drop earlier in the day.
(Reporting by Vikram Subhedar; Editing by Sanjeev Miglani)