Hi!
BlizzardPPC's give off a lot of heat and take a lot of power so an
A1200 Tower system is necessary to run such a device. Theoretically, if you put it in a desktop, you will need a lot of cooling and noisy fans. You will also need an external powerful power supply such as the old Goliath/Powerbox variety. To be honest I wouldn't recommend the desktop option.
Official Amiga A1200
Kickstart 3.1 ROMs don't have stickers on them - may be EEPROMs. Make sure the
AmigaOS 3.1 disks are originals.
