With the new operating system, Microsoft is offering plenty of new graphics tricks, including translucent windows, animated flips between open programs and "live icons" that show a graphical representation of the file in question.
But before Vista will display its showiest side, known as Aero, it will run a check to make sure the software was properly purchased.
"Those who are not running genuine Windows will not be able to take advantage of the Windows Aero user experience," a Microsoft representative told CNET News.com on Wednesday.
The move is the latest salvo in Microsoft's broad attack on those who use unauthorized copies of its operating system. In the fall of 2004, Microsoft began testing the Windows Genuine Advantage program, designed to verify that a particular copy of Windows is legitimate.
At first an optional program, the piracy check eventually became mandatory for many types of Windows XP downloads, but was not required to run any aspect of the operating system itself. Microsoft has identified reducing piracy as a key way for the company to grow its sales of Windows, which is already used on more than 90 percent of personal computers.
But it's not just pirates who will be blocked from Windows' fanciest graphics. The Aero display also won't be available to those who buy Windows Vista Basic, the low-end consumer version of the operating system. And even those with higher-end versions won't be able to see the fancy graphics if they don't have enough memory, lack sufficient graphics horsepower or have a graphics chip that doesn't support a new Vista driver.
Microsoft has not issued the final hardware requirements for Vista itself, which is due to go on sale to consumers in January. However, the company has issued some guidelines for Aero, as part of a draft product guide that was briefly posted on the Internet this week.
To run Aero, a system will need to meet some pretty specific and arcane requirements, including memory bandwidth of at least 1,800MB per second, Microsoft said in the document. The product guide said that Vista would include a tool for measuring this, but Microsoft did not offer further details on how consumers with existing PCs will be able to see if their machines meet the standard.
A Microsoft representative said on Thursday that more information for existing users will be available soon. There are diagnostic tools available on the Web, such as SiSoftware's Sandra, that provide memory bandwidth benchmarking information.
Microsoft is also building a performance measuring tool within Vista that will provide a numeric rating of how Vista-capable a system is.
The system will need a graphics chip with a Vista-specific driver, as well as a varying amount of minimum graphics memory, depending on the size of the monitor. A computer with a single display of 1280-by-1024 pixels or less, for example, must have 64MB of graphics memory. For a larger screen, 256MB may be needed, as well as additional memory for secondary displays.
A PC with shared memory--that is, memory that is used both by the main system and by the graphics chip--can also work with Aero. But it needs to have 1GB of dual-channel memory, with at least 512MB of that memory available to the main system.
Microsoft said that the Aero requirements stated in the product guide are not final. The Redmond, Wash.-based company has so far only released guidelines for machines that will display a logo indicating their Vista-readiness.
"A draft version of the Windows Vista Product Guide was posted inadvertently and includes information that is not yet final," the Microsoft representative said in an e-mail. "To date, we have only provided hardware guidelines as part of our Windows Vista Capable PC efforts. The Windows Vista Capable PC Program provides information to customers about PCs they can buy today that will be able to run Windows Vista."
Those Aero requirements are not easily understood by buyers or computer salespeople, said Michael Cherry, an analyst at market research firm Directions on Microsoft. He said, for example, that he has no idea how much memory bandwidth his computer has. "I wouldn't even know how to begin to measure it."
Cherry said that Microsoft still has work to do to translate these requirements into something that is understandable to the average PC user.
"I don't want to be an electrical engineer to figure this out," he said.