Well... there are 2 types of heatsinks comming with the 3640, one have a fat an low sink while ther other is smaller and taller. Either will fit in an A3000 mut only the thin one will fit in an A3000 unless you mod something. Commodore didn't release the 3640 for the A3000 simply cause they didn't find it safe... users are welcome to do what they want with their machine but I'd say try create good (ehm... better) airflow in the machine and add a fan if possible (doesn't have to sit right on top of the heatsink to still do good).
