The fourth entry in More Fun Fixing It’s C64 color RAM Repair Challenge opens with another Commodore 64 pulled from the repair pile, ready for diagnosis. The host’s mission is clear: restore each standard C64 first, building confidence before moving on to the rare Silver Label models waiting in line. Every repair so far has offered a unique puzzle, and this one promises the same—a mix of curiosity, patience, and a dash of solder smoke.
The machine boots with flicker and weird artifacts. A handwritten note claims the PLA is bad, so that path gets explored first. Next comes microscope time, reflowing several suspect joints, and reseating socketed chips. Then diagnostics begin to disagree, pushing the search away from the Super PLA on this shortboard.
Dead Test flashes point toward memory trouble. Matt Desmond’s tools echo the same hint. The board shows prior work around the CIAs and DRAMs, adding another wrinkle. Still, systematic checks keep progress moving.
The host pulls the DRAMs, tests them, and reinstalls the good parts with fresh sockets. A continuity check catches one missed joint, which quickly gets fixed. Then comes the real insight. Color memory fails repeatably, even with reflowed pins.
Replacement becomes the smart move. A known good 2114 goes in after careful desoldering with a slimmer nozzle. Fresh solder fills each via cleanly. The board stays stable, and nothing lifts.
Power on. The display finally settles into a clean screen. Diagnostic cartridges pass with green bars across the board. The repaired machine joins its healthy siblings, ready for more testing and real use.
Lessons stack up. Assumptions can waste time. Clear notes help. Patience wins. The creator owns every misstep and turns it into a teaching moment. C64 color RAM now sits on the early checklist for similar faults. Expect more fixes soon, then a shift to those famed Silver Labels. C64 color RAM strikes, but persistence wins.
