Hello,
Your case is not really a case that anyone else is using nowadays: if we are talking about the same monitor, this is a soon to be 15 year old device you are now plugging on a <1 month old operating system (Windows 10 Insider Preview with beta graphics drivers).
I hope you can understand we unfortunately have to prioritise based on the number of people impacted and despite looking we don't have such monitor in store as Apple made the ADC obsolete 11 years ago.
Furthermore, the ADC -> DVI adapter, even if extremely costly at the time is very particular in the way it works, or doesn't...
The DXdiag results are a red herring. DXdiag doesn't understand what is plugged in.
1. Can you please explain what is your current setup? What is the chain of connection?
I'm confused by your mention of a DisplayPort adapter and how it has an impact on another monitor as the HP NL571AA is a USB->DVI adapter.
2. Is your monitor really the following?
http://www.everymac.com/monitors/app...lay_17_fp.html. What we can read says 2001 so it should be.
3. Can you please give up to date logs? There are too many variables which changed to make the old one useful. FWIW, in that first log, not only was your screen recognised properly, but the DisplayLink adapter declared outputing 1280x1024x32@60 (monitor APP9217 (Apple Studio ) modes: 1280x1024@60.0197)... So the issue seems more located after that. Do you have any information we could have missed?
Kind regards,
Alban