Did you set the CPU sync jumpers on the motherboard? For the A3640 it needs to be set for external sync. For an 030, and I beleave the 060 as well need to be set for internal sync. Also both jumpers need to be set to the same position, they are right next to each other.
J100 Pins 1 and 2 CLK90 Clock Source is Internal
Pins 2 and 3 CLK90 Clock Source is External
J104 Pins 1 and 2 CPU Clock Source is Internal
Pins 2 and 3 CPU Clock Source is External
Information here
http://www.amiga-hardware.com/showhardware.cgi?HARDID=4Diagram here
http://www.amiga-hardware.com/downloads/a4000tmbdiagram.gif
