This could also be caused by a bad connection or poor contact between the wire and the receptacle. Notice the side is melted, where the terminal screws would be, thats where the heat would be generated. When you put a load on it and electrons have to jump the gap it arcs and generates heat. Load is also a factor, on this receptacle or any downstream, but the melting on the side might be caused by arcing.
I’m running 70b on two used 3090 and an a6000 nvlink. I think i got these for $900ea, and maybe $200 for the nvlink. Also works great.