Napster and Virgin Radio are launching a digital music chart, entirely based on Napster's online sales.

The first chart will be broadcast on Sunday August 29 at 7pm - just days before the Official Chart Company launches the official digital download chart. The latter chart is scheduled to launch in September, and will collate its data from sales reported by all the main market players, including Apple's iTunes, OD2 and Napster.

The Napster Online Music Chart on Virgin Radio will have one unique factor - it will register full-length streams, subscription and permanent downloads. Every week the top 20 tracks will be revealed during the show.

Napster and Virgin have other plans, revealing this alliance to be: "The first step in a unique strategic marketing partnership," between the two firms.

Napster UK vice president and general manager Leanne Sharman said: "As well as hitting our core demographic and having millions of listeners, Virgin Radio enjoys over one million unique online visitors a month, making it an ideal brand partner for Napster."

Other marketing initiatives engaged in by Napster include: a partnership with UK electronics retailer, Dixons; a partnership with broadband provider, NTL; and a promotion with The Sun newspaper.