Sega Columns arcade pcb repair

No boot with black screen, logic probe showed the 68000 CPU was stuck in halt mode. Piggybacking known good RAM over the TMM2063 chips next to the 68000 CPU allowed it to boot though with bad colors.

Piggybacking known good 6116 compatible RAM over the palette RAM in the middle of the board fixed the colors.  These 3 RAM chips were then replaced and game was perfect.