The 2 ram boards, the pattern board and the cpu board are interchangable with a Wizard of Wor machine. I found out which ram board was bad by swapping them in my WOW one at a time. Same thing with the pattern board. Once I narrowed it down to the bad ram board I took a new ram chip and piggybacked it on top of each soldered ram chip one at a time and held them together with a piece of tape and then powered up the game. When you get to the bad ram chip you will see a change or fluctuation of the problem on the screen and that will tell you which ram chip is bad. Then it is just a matter of cutting the bad ram chip off the board, sucking the legs and solder out of the holes, adding new chip socket with a new ram chip and it should be fixed. Thats how I fixed my Gorf. Of course I also have a WOW so it makes it easy to troubleshoot both games. Even if you don't have both games if you suspect either ram boards are bad you can still use this piggybacking the ram chip trick to fix your Gorf or WOW. It will just take a little longer.