HP is attempting to stop Acer, which has become a major global competitor in the last few years, from selling certain products in the US. 

HP says the products, which include desktop and notebook computers as well as media centres and others, infringe on five HP patents issued between 1997 and 2003.
A statement from HP says it "is taking necessary action to protect its intellectual property against unauthorised use" by Acer.
Acer is currently the world's fourth-largest PC vendor. It has been particularly successful in the East, Europe and Middle East/Africa, but has recently started making inroads in the US market as well.
The lawsuit was filed in a Texas federal court on Tuesday. The patents at the centre of the controversy relate to optical data storage, circuits and methods for reducing computer system power consumption, multiple processors in computer systems, and a method for attaching devices to a digital serial bus.
Acer is expected to comment on the lawsuit today. It will also release its 2006 earnings later today.