I got the same behaviour with my Microbotics 1230XA, i.e. yellow screen and no booting. If I remove either the Delfina or the turbo card, the computer boots fine. I now have an Apollo 1260 which works great together with the Delfina.
I'm a little bit surprised that your Blizzard card does not work, because I thought this was only an issue with the Microbotics card. I know there are some issues with the clock port on some Escom motherboards, so you might want to investigate that if you have an Escom Amiga.