A slow year for the PC industry got a lot worse Tuesday, after Microsoft ( MSFT) announced that it was delaying its consumer version of the Vista operating system until January 2007.

Though the move postpones Vista's release date by only a few weeks, it means that PCs won't be available with the new OS during the all-important holiday season.

Shares of most major PC-related stocks lost ground on Wednesday, with Dell ( DELL) and Hewlett-Packard ( HPQ) down 12 cents and 27 cents, respectively, in midday trading.

Intel ( INTC) was up 2 cents at $19.80, while Advanced Micro Devices ( AMD) was down 13 cents at $34.31.

The announcement added negative sentiment to what was already looking like a gloomy year for the PC industry. Earlier this month, industry research firm Gartner projected that PC sales in 2006 would grow 10.7%, compared with 15.5% the year before.

And on Monday, Lehman Brothers reduced its own PC forecast for 2006 to 9.8% growth vs. a previous estimate of 12.4% growth.

Yet Lehman Brothers, along with several other Wall Street analysts, did not pare back its expectations about the PC industry further in the wake of the Vista announcement.

While the Vista delay clearly doesn't help business in the PC market, it seems that expectations surrounding Microsoft's biggest operating system upgrade in years were somewhat restrained from the outset.

The Vista delay "does not change our view on any of the computer (Dell, H-P) or PC-chip (Intel, AMD, Micron ( MU)) stocks we follow, as we had not incorporated any assumption of a better-than-expected surge in PC demand from Vista in the second half of the year," wrote A. G. Edwards analyst David Wong, whose firm owns long and short positions in Dell and has provided noninvestment banking services to H-P in the past 12 months.

Consumer PCs account for only a small portion of Dell and H-P's profit, said Wong, adding that only 9% of Dell's operating profit and less than 7% of H-P's operating profit came from consumer PC sales in the January 2006 quarter.

Goldman Sachs analyst Laura Conigliaro also predicted a minimal impact on Dell and H-P.

"Although the absence of a consumer tailwind from Microsoft's Vista during the holiday shopping season takes away a source of upside during the quarter for H-P and Dell, the amount of business pushed out is unlikely to impact earnings at either company," Conigliaro wrote in a note to investors.

According to Conigliaro, Dell would have to lose nearly a third of its consumer revenue to reduce its EPS by a penny. And any potential upside at H-P is based on enterprise hardware and printing rather than on consumer PCs, said Conigliaro, whose firm has had investment banking relationships with Dell and H-P within the past 12 months.

Atlantic Trust Stein Roe's Chuck Jones, whose firm owns Dell shares, said he didn't believe the delay would skew the numbers significantly at any of the major PC vendors.

"Yes it affects consumer PC buying during the holiday season," Jones said. "Am I going to get worked up about it? No."

But with Vista out of the picture, PC makers will now have to rejigger their holiday and product plans.

H-P said it still expected the holiday season to be its PC group's strongest selling period, but said it was still too early to share any details on specific product offerings or upgrade plans at this time.

"But with more than 90 percent of our consumer PC portfolio qualifying as 'Vista Capable,' customers concerned with future compatibility with the new operating system will be able to purchase with confidence that their H-P system will continue to serve them well as they look to move to Vista and other system upgrades of their choice," an H-P representative said in an email.

A Dell spokesman said it was too early to speculate about how the company's product plans would change for the 2006 holiday season. He said that Dell will be ready as soon as Microsoft ships the product.

Without Vista, said analyst Sam Bhavnani of Current Analysis, PC retailers will likely have to shine the spotlight on low-end systems this holiday season -- the PCs with $299 price tags.

"Those sales aren't going to be impacted because people are going to buy those PCs -- no matter what operating system it's running," Bhavnani said.

Of course, while this may allow PC vendors to keep their unit sales volumes up, profit margins may not fare as well.

"You make much less money on a $299 system than you do on an $1199 system," said Bhavnani.

Other technology innovations could help maintain demand for higher-end systems through 2006, even without Vista.

A.G. Edward's Wong pointed to notebooks with new dual-core processors from Intel and AMD, as well as home entertainment systems based on Intel's Viiv platform, as drivers of PC demand in the second half of the year.