[sawdust]

ok you are using the Messiah 2 wright? it sounds like you have a power wire too close to a chip on the main board that is makeing the screen fuzz when u try to boot a game so try this
first keep the wires as short as possable
see are there any solder bridges use a magnafining glass and look closely
do u have good conection with all the wires and what they are soldered to did u use flux when u soldered to copper pads on the board did u clean them before
go over the board with a good set of clocks test all the wires going to the chip
move the wires that are close to the large black chips on board away from them
if all this doesn't work wrap some wire around the SEALED power wire and solder the 2 ends to the copper ground strip on the edge of the board the power wire should have NO BREAKS IN THE CASEING and the ground u are putting around it should have NO Conection with the power wire only do this if non of the above work