UPDATE 3-CBS posts $12.5 bln loss, but commits to dividend

* Q3 loss $18.58 per share due to large write-down

* Adjusted EPS 40 cents matches analyst expectations

* Says committed to dividend and cutting costs

* Shares rise 6 percent, rallying from recent lows (Adds executive, analyst comments)

By Paul Thomasch

NEW YORK, Oct 30 (Reuters) - CBS Corp (CBS.N) posted a $12.5 billion quarterly loss, hurt by a massive write-down and the deteriorating advertising market, but its shares rose 6 percent after its executive chairman and largest shareholder Sumner Redstone affirmed his commitment to the company.

Investors also appeared relieved that the TV and radio broadcaster reiterated its plans to pay a dividend, even as it took a previously announced $14.1 billion noncash charge in the third quarter for goodwill and other assets that lost value because of the economic turmoil.

But some analysts, including Caris & Co's David Miller, said investors may be placing too much emphasis on the CBS dividend.

"We find it near incredulous that the Street is placing so much emphasis on CBS' juicy 12.4 percent dividend yield, and little emphasis on the notion that CBS will see a severe contraction in earnings next year," Miller wrote.