BOSTON, US - Two top research firms are cutting forecasts for 2009 personal computer sales, expecting shipment values to drop next year as the weak economy discourages some buyers and tight credit thwarts others.

IDC, which tracks sales of technology products, said on Wednesday it expects global PC sales to fall 5.3 percent next year to US$267 billion ($408 billion). It had previously forecast a 4.5 percent increase.

Gartner analyst George Shiffler, whose firm is preparing to cut its forecasts, said he expects 2009 to be the industry's toughest in at least seven years with sales of high-end PCs falling sharply.

"You're going to get a lot of price competition as the market deteriorates," he said in an interview. "We think that vendors will be moving their portfolios to lower-priced products and maybe some outright price cutting. Average sales prices are going to suffer."

The PC industry's woes may hurt sales at top makers Hewlett-Packard Co, Dell Inc, Lenovo Group Ltd, Acer Inc and Apple Inc. Microsoft Corp, whose Windows operating system runs more than 90 percent of PCs, is also likely to take a hit.

Shiffler, Gartner's top PC analyst, said the firm is likely to issue a forecast that spending on PCs would drop at least 6.5 percent to about US$230 billion next year.

Gartner's new forecast would be for unit sales to grow 5 percent to 312 million desktop and portable machines next year, Shiffler said.

But if the economy continues to deteriorate, then global spending on PCs could fall 10 percent or more and unit sales could also decline for the first time since 2001, he said.

"If the slowdown spreads to emerging markets and has significant effect there, that's when you are talking about negative unit growth," he said.

IDC's forecast calls for total unit shipments to rise 3.8 percent next year, down from 12.4 percent growth in 2008.

"What has changed is primarily a reaction to the economy," said Loren Loverde, an analyst with IDC, which last issued its forecasts for PC sales about three months ago.

IDC had previously forecast unit shipment growth of 13.7 percent.

There is a discrepancy between the growth in units sold and value of those PCs because prices are falling as consumers and businesses budget less for new PCs, Loverde said.

"Buyers are watching their pockets a little more closely. They are less inclined to upgrade or get that faster processor," Loverde said.

The credit crunch is also hurting the industry, he said.

"A company or individual might want a PC. If they could get the same credit terms as last year they might buy a PC, but credit is tighter," he said.

HP shares rose 1.2 percent to $34.67 on the New York Stock Exchange shortly before the close. On Nasdaq, Dell fell 0.67 percent to US$10.45, Apple rose 2.8 percent US$95.08, and Microsoft gained 3.1 percent at US$19.74. Lenovo fell 3.2 percent on the Hong Kong Stock Exchange, while Acer shares were flat. --REUTERS