Microsoft has set its pricing for Windows Vista, about a week after online retailer Amazon.com disclosed the OS's price on its Web site.

Microsoft's suggested retail pricing for Windows Vista is as follows: $399 for Windows Vista Ultimate, $299 for Windows Vista Business, $239 for Windows Vista Home Premium and $199 for Windows Vista Home Basic.

Upgrades to Windows Vista from XP are $259 for Windows Vista Ultimate, $199 for Windows Vista Home Premium and $99 for Windows Vista Home Basic.

The prices are the same as the ones listed on Amazon.com's Web site last week, except the online retailer listed an upgrade for Vista Home Basic as $0.95 more.

The company also expanded the tester base of Vista to about 5 million users as it begins gearing up for Windows Vista's widespread release, which is scheduled for early next year.

Amazon.com is already taking pre-orders for Vista, and lists on its Web site that the OS will be available on Jan 30, 2007. Microsoft has not given a firm date for Vista's release, but is targeting sometime in January for the OS's general release. The company plans to release Vista to business customers in November.

On Friday Microsoft made available Release Candidate 1 (RC1) of Windows Vista, which means the OS is in its final testing phases. The release was initially made available only to about 15,000 users who are in Microsoft's TechBeta and Technology Adoption Program (TAP) program, but on Tuesday the company expanded that release to members of the Windows Vista Customer Preview Program.

The company also will post Windows Vista RC1 to its Microsoft Developer Network (MSDN) and TechNet Web sites so subscribers of those programs can download it. The company said that about 5 million users worldwide will have access to RC1 as Windows Vista goes through its final testing.

Shanen Boettcher, general manager of Windows client product management, said the early feedback Microsoft has received on RC1 has been positive. He said Microsoft will determine whether to make a second release candidate available based on tester feedback to RC1.

Windows XP had two release candidates before it was shipped to manufacturing. Analysts have said that if Windows Vista follows the same path, it will be a tight squeeze for Microsoft to get the OS out according to its current schedule.