Alright, time to slice this puzzle. First, disconnect the cabinet and strip the outer shell—no need for the fancy metal frame. Pull the power supply and test its output with a multimeter; if it’s dead, that’s your first dead end. If the power’s okay, move to the main PCB. Look for obvious signs—burn marks, swollen electrolytics, or disconnected components. Mark any missing ICs; replace them only if you’re sure they’re the culprit. Next, isolate the video and audio sections. Check the sound ICs and the oscillator—those are usually the weakest links. If the board powers on but no sound, swap the audio IC with a known good one. For video, test the LCD/CRT driver if it’s a CRT cabinet, or the LCD panel if it’s a newer model; swap or solder a new driver IC. If the board still refuses to hum, it’s likely the main CPU or ROM. Test the CPU with a logic analyzer or simply check for voltage on the core pins. If the ROM is readable, you might even dump it with an old programmer. Finally, reassemble in small steps, testing at each stage. If you’re still stuck, it’s probably a deep‑seated fault—maybe just a bad power supply, but don’t quit before the final swap. That’s the plan, stick to it and keep the process lean.