I wasn't even thinking of installing the card in an se or lc. I used a software called slots I downloaded somewhere and I was wondering if it was any good and if it was the only way to test cards.

Unfortunately, I can't do a clean install right now as I don't have a Zip/Jaz or even an external SCSI hard drive. I will try to get one in the near future, though.

By the way, My SE/30 is running system 7.5.3. It is clean enough I think

The 30-21 is the same card, with a few differences though: more VRam, and another rom chip. I thought it was compatible with all kinds of displays.

Oh and one detail i forgot to mention about the radius card: I had trouble some trouble with it in the beginning. I think that it appeared on the monitor control panel only when I selected the right Color QuickDraw profile, but then when i tested it again, without any drivers installed, I could still see it using "Slots". I tried every single profile (multi sync and fixed frequency), but nothing appeared. I even rebooted each time as I heard somewhere that changes made on the config for the Lapis needed a reboot (whereas Radius cards didn't need a reboot)

I will try to check the solder joints on the PDS connector. Since it was pulled from a working SE/30, the guy who sold it on ebay may have damaged it, who knows...

Meanwhile, I will disable every single extension apart the Colorserver 17 control panel.

Thanks anyway for your answer(s)

I'll keep you posted.