Well, I know that my a1200 can output to this PC monitor I have, using Multiscan, DblPal and VGAonly. But when I try and use my Amiga 4000, trying each of those modes, and making sure I have VGAOnly in my Devs/Monitors drawer it just won't play ball. I tried everything I could think of to make it work - but nothing. That's why I thought it could be the adaptor. The a4000 adaptor is buffered in some way, which I was hoping could just tweak the signal to allow it to output a display.
Any suggestions GREATLY appreciated!