ignore previous for this the one program I was using stated 126 in the GUI for some reason, use bits 127 and 128. Zero 127 increment 128 by 1. So if 01 then 00 if C1 then C2.
Although I disabling 126 would disable the second page anyway....
Played around a bit with EDID again in registry, monitor inf and overridedEDID values, again no luck.
EDID in monitor, hardware EDID emulator or modifying the nvidia driver are best bet for looking into getting this to work in the future.
Looks like the EDID in my monitor is read only, had no luck changing this with software, would appear to write but then error out on verifying.
Can't find any displayport hardware EDID emulators. There was the displayport detective but can't find those anymore.
If you read the Nvidia Release notes they do mention how for monitors and TVs that have issues they update the driver for those typically making HDTVs show up as DVI which gets them to work but of course disables HD audio, so easiest route would be to fake your monitor to the EDID of those monitors or HDTVs.
Done for now with testing until next time:
Current config is DVI to DVI (1920x1200 @ 60hz) to one monitor and Displayport to Displayport (2560x1440 @85hz) to another both with scaling using the 355.98 driver.
Using Refreshlock for the 2560x1440 monitor to limit refresh rate to usable values on this XB271HU to eliminate black screen issue.
The displayport to HDMI active adapter does work to eliminate black screens since it's limited to 60hz at 2560x1440 but no scaling available so another potential option would be for a programmable active adapter or EDID emulator that can change the bit or switch to DVI but AFAIK it needs to be active throughout the chain so if using a EDID emulator then it needs to be active.
Forgot, one of the features of the Quadro cards is the ability to load EDID from a file in the Nvidia Control panel so if anyone has a Quadro they want to use in XP then that would be a good test for modifying the bits to disable audio or using an edid that the nvidia driver has set as not HDTV.
Need to look into the registry for EDID change again since this page mentioned XP 64bit, I doubt he'd mention it if it didn't work BUT this was for an ancient Nvidia driver version:
https://www.nvidia.com/en-us/geforce/forums/d … onnection-or-f/