As the title said I can't get my secondary video card to detect any monitor connected to it in windows 10,

Specs:
Prime B350-Plus
1700X (stock)
32 GB ram (2 sticks 2400mhz)
Samsung 960 EVO M.2 (boot drive)
RX460 4GB (primary) with 3 monitors connected.
HD 3600 (4GB), does not detect monitor on either DVI plugs.

windows 10 doesn't detect any monitor connected to the video card, the monitor states no connection.
I have tried also with an older video card, don't remember the specs, and it also did not work.

Do I need to buy a new video card just to get the 4th monitor to work?
I would prefer not to, however if i must....

google didn't help, it keeps referring to an older control panel display settings, that is no longer there with the last windows update.
Thanks for any feedback you provide.