Vista rating tool is tweaked

…relies heavily on graphics chip horsepower to generate its Aero user interface.

"It should be very clear to everyone how important graphics are," said Andrew Dodd, a software product manager at graphics specialist ATI Technologies.

Microsoft has also clarified its intent for the program and offered up more details on how it will work.

"Windows Experience Index is designed to help average consumers easily understand their Windows Vista PC's overall performance, and to simplify the process of determining whether certain software applications will run smoothly based on their system components," it said.

It added that computer makers and retailers can use Windows Experience Index to "help customers understand the general performance capabilities of a Windows Vista PC and the types of experiences it can support, relative to other Windows Vista PCs they offer, thereby enabling easy-to-understand differentiation".

Software makers will also benefit, as they can use the scores as to communicate the minimum and recommended system performance for their programs, Microsoft said.

Scores on the doors
The initial version of the tool will offer a 1-to-5 ranking, but additional numbers will be added over time, Microsoft said. That means a PC that gets a "3" today will continue to get a "3", but eventually there will be computers that rank a "6" or a "7". "We will introduce new scores (6.0-6.9, 7.0-7.9, and so forth) periodically as new hardware component performance capabilities increase," Microsoft said in a statement. "The existing numbers will simply remain defined 'as-is' (ie the performance metrics for a 3.2 will always be the same regardless of how many new numbers are added). We created this scoring system with upward scalability and hardware technology advances in mind."

The company also offered some assessment of what the ratings mean, though it did not provide a complete breakdown of each score and what it signifies.

"Using this base score, a customer can then determine if their machine will support their desired experiences (ie, if a person uses their Windows Vista PC for office productivity and Web browsing, a base score of 1-2 would suit their purposes; or if another person uses their Windows Vista PC for HDTV recording and 3D gaming, a base score of 4-5 would suit their purposes)," Microsoft said.

Dodd said ATI's main concern is that the score will represent an accurate reflection of what the graphics chipmaker's components can do in real-world use.

"I know they are still making changes to what determines whether you get a '4' or a '5'," he said. "As long as Microsoft makes it clear what each rating means and why they are getting that rating, it is a very good thing for end-users."

AMD's Simmons said that even if the tool underestimates the importance of a PC's processor, it is still a benefit if it leads to fewer returned computers and a boost in customer satisfaction. Although it will ultimately be up to PC makers and retailers how to use the scores generated by the Windows Experience Index, Simmons said she envisions the ratings appearing on the kinds of fact sheets that accompany a PC on store shelves.

"Even if it is not necessarily good for the CPU itself, it is good for the industry," Simmons said.