hi . u didnt say if you just brought the blizzard ppc card.
if so when brought mine it brand new all those years ago.
it just didnt go with my orginal motherboard rev id 4
l thought brought a dud card.
so went got second hand 1200 and worked right away.
its been going ever since many years with out any problems.
just suggestion.
also go into the ppc boot menu and try setting up diffrently ie 70 ns memory no maprom etc . also disable the scsi . just ideas.
hope u work it out soon am sure u will. :-)