Hi,
I used to use a CV64/3D in my A4000ec030 w/OS3.0. I suggest booting with no startup-sequence, and starting the CGX driver from a shell. Since I had a scan-doubler as well, I used to see the screen flicker a bit as the scan-doubler initialised (?) along with the card. Even if you don't have one I'm sure you should see SOMETHING.
Then ... uhm.. sheesh it's been so long; IIRC you should go through your startup-sequence manually, running the iprefs command, which should come up saying: please close all windows so that iprefs can change screenmode (or something like that). THAT way you should end up with a bare bones screen (that you can't do anything with) but if you can get that far and can see it's changed to a higher non-PAL res, you know the card is working.
But I'd be inclined to check for a virus. DO check for viruses.
Good luck,
- Paul
