In one of my rigs with only 3 GPUs I'm using (for about 6 months) risers version 009s that have 2 LEDs (red 3.3v, blue 12v).
After a periodic maintenance (cleaning) the blue LEDs (12v) of two risers do not light up anymore even though for now everything works well as before, global average hashrate has not changed.

Does anyone know if I still have to replace them?