I’ll try with a couple other monitors (the one I’m testing is a pretty old HP, but I’m using HDMI to DVI for it).
I also should note that following the How to use external gpu on VisionFive v2 - #24 by geerlingguy thread, I’m actually able to get output through the same monitor from an AMD Radeon graphics card—though I can’t get a display manager to run (something with the PVR driver I guess, conflicting with radeon).