Elen, Any decent SI simulation tool should go to at least 10 GHz. (SpecctraQuest does. Others do also.) The limitations are more likely to be in the IBIS models than in the field solver or transmission line models. It takes good IBIS models (based on good transistor models) to simulate=20 effects at those speeds. - Lynne Dr. Lynne Green Senior Member of Consulting Staff PCB Systems Division Cadence Design Systems, Inc. ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List archives are viewable at: //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu