Taiwan's UMC, the world's No.2 contract chipmaker, booked its smallest monthly sales in five months in November, showing weaker demand for some technology products before the year-end shopping season.

Analysts expect UMC and sector leader TSMC to see flat or slight declines in fourth-quarter sales from the third quarter, with a strong Taiwan dollar also threatening to squeeze their sales and profit margins.

United Microelectronics Corp (UMC) had sales of T$10.44 billion ($344 million) last month, up 14 percent from a year ago but down from October's T$10.7 billion, the company said on Wednesday, without giving other details.

Growth momentum is slowing but that's within our expectations, said Andrew Deng, analyst at Taiwan International Securities.

The PC and TV sectors remain weak even though sales of some new smartphones are pretty good.

UMC, which counts Taiwan's Mediatek Inc and U.S. Xilinx Inc among its major clients, had predicted its fourth quarter wafer shipments will fall by mid single-digit percent from the third quarter.

Market players have largely priced in UMC's November sales, which matched analysts' expectations. UMC shares fell 0.9 percent on Wednesday in a flat TAIEX. Shares of TSMC, whose November sales are due out on Friday, was unchanged.

UMC's sales amounted to T$110.25 billion in January-November, up 39 percent from the year-ago period, the company said.

For a table on the company's website, see

http://www.umc.com/English/investors/2010_Montly_Rev.asp

Separately, Quanta Computer Inc, the world's top contract laptop PC maker, posted an 11.7 percent year-on-year rise in November sales, a rate that was slower than the previous few months.

(Reporting by Baker Li; Editing by Jonathan Standing)

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