I am quite sorry, R4101 should be R4104.It is behind the backside of smps IC. To answer your question,R4104 supplies the drive voltage to the STK730-010 smps IC,without that excitation voltage chip(STK730-010) will not function,hth and sorry about the mistake. Charles Betzler Best Electronics repair1@xxxxxxxxxxxxx ----------------------------------------------------------------------------- Lost Password: http://www.tech-assist.org and select "Login Problems?". Email Archives: //www.freelists.org/archives/techassist/