UPDATE 1-Taiwan's TSMC posts biggest profit in one year

* Q3 net profit T$30.55 bln, mostly in line with mkt forecast

* Raises 2009 capex to $2.7 bln from $2.3 bln

* Stock down 0.3 pct before results

(Adds quotes and details)

TAIPEI, Oct 29 (Reuters) - Taiwan's TSMC (2330.TW), the world's top contract chip maker, met market expectations as it posted its biggest quarterly net profit in a year, after making more advanced chips for new PCs and other high-tech gadgets.

Analysts expect TSMC's sales to be flat or weaken in the fourth quarter as technology demand typically slows from a peak in October through into the first quarter.

For next year, however, new technologies should further cut manufacturing costs and help the foundry win new orders from clients, who are selling more powerful chips used in a new generation of computers, mobile phones and flat-screen TVs.

A spate of bullish news from global technology firms has been positive for foundries such TSMC and UMC (2303.TW), which supply chips to fabless chip designers and chipmakers that are stepping up outsourcing to cut costs.

Taiwan Semiconductor Manufacturing Co (TSMC) (TSM.N) earned a net profit of T$30.55 billion ($904 million) in July-September, higher than the second quarter's T$24.44 billion but slightly lower than T$30.57 billion a year ago, the company said on Thursday.

Analysts had expected TSMC to earn T$31.2 billion in the third quarter, according to a consensus forecast from brokers as per Thomson Reuters I/B/E/S.

"As demand outlook continued to improve, third quarter saw a solid growth in demand for semiconductors across all major applications," TSMC said in a statement.

TSMC raised its 2009 capital spending to about $2.7 billion from its previous forecast of $2.3 billion.

On Wednesday, smaller cross-town rival UMC (2303.TW) (UMC.N) forecast its wafer shipments would fall slightly in the fourth quarter. [ID:nTP112950]

TSMC's results came after the close of trading hours in the Taipei market. TSMC's shares shed 0.3 percent versus a 2.4 percent drop in the main TAIEX .TWII.

In Taipei, TSMC's shares gained 19 percent in the third quarter, similar to the main index's rise. (US$1=T$32.6) (Reporting by Baker Li and Argin Chang; Editing by Anshuman Daga)