What you mean ground? PSU is INTER-TECH Booster SPS-520 AC 115/230V, 50/60Hz, DC 2.2/5 12V, 520W, Retail, Passive PFC, 1x80.
Also maybe offtopic, but i.e. when fridge turns on for freezing, or you just turn on or off light switch, the monitor blinks for a millisecond, the speakers glitch for...