Ok...here's the problem The machine come up with garbage on the screen.It would also seem that the video is inverted, I can see the retrace lines etc, so the horizontal blanking is not working either by the looks of it. What I suspect is wrong is that either U42 (the 6845 labeled in my machine as a motorola SC80757P) or U102 (the 4.3 video support chip) is faulty (or both?). Does anyone have any info on U102 (what is it..can I get another?) or any other thoughts. Some other notes are. 1. It seems to boot (I get a very crappy tandy logo in inverse on the screen) though the screen is so unstable as to be unreadable. 2. It does not matter if it is in 64 or 80 column mode, the video is still crap. 3. I suppose the Char generator rom could also be a problem Any help would be appreciated. BTW does anyone have the diagnostic disc for the 4/4P ? Cheers +----------- Keith Whitehead -----------+ | Physics and Chemistry Depts | | Massey University | | Palmerston North | | New Zealand | | | | Ph +64 6 350-5074 Fax +64 6 354-0207 | +------------------------------------------+