the new card is a TurboGX so i can get color graphics.

looks like the people who designed it left their names on the circuit board. i guess some of them are crossed out because they left the team?

aaand i get a black screen. that's odd.

hmm, maybe my adapter board (configured for H/V sync) will not work with this card that puts out CSYNC only.

no CSYNC comes out. checked it with a scope. OK, maybe the monitor sense pins being floating is a problem? i think it should still come up even with nothing (1152x900 66Hz).

that wasn't it either. no change.

quick sanity check with the old video card, and that still works OK.

could be an old PROM version. the previous screen shows ROM Rev 1.1, but here it looks like I need PROM 2.0 or higher.

PROM is 525-1043-07, which is for a SPARCstation 1, not a 1+. uhh, looks like i actually own a SPARCstation 1 but the lid has the wrong logo on it!

looks like The Retro Web has a PROM image i can use.
https://theretroweb.com/motherboards/s/sun-sparcstation-1

new PROM programmed and ready to go.

with the monochrome video card, the new PROM boots up. NVRAM is invalid since it probably remaps everything, but at least it is smart enough to recover the MAC address. i was expecting to have to reconfigure the whole thing manually, because Sun.

yeah looks like the color card works (this is the green video channel) but i will need a way to convert the sync signals to this monitor.

@tubetime indeed looks green