AMD has been accused of patent infringement for the second time in less than a month. Having found itself on the receiving end of a lawsuit from intellectual property holder Opti earlier this month, AMD was this week threatened by MicroUnity Systems Engineering.

MicroUnity claims a whole heap of AMD CPUs, new and old, which support 3DNow! and provide compatibilty with Intel's SSE technology infringe upon a dozen of its patents. The lawsuit filed with the US District Court for Eastern Texas even lists AMD processors that have yet to come to market.

The plaintiff said it wants a jury trial, and it's asking for damages should the case go its way.

MicroUnity sued Intel on much the same grounds back in March 2004. Then, it claimed seven of its patents had been violated by CPUs that support HyperThreading and the first two versions of SSE.

In the summer of 2005, Intel settled with MicroUnity by paying it $300m. ®