I do not build a mining farm with a consumption of 2-3 kilowatts. It is better to make 2 mining farms with a server power supply of 1200-1600 watts. Maybe it will be more expensive by $ 100, but it will be more reliable.
I have had no problems building mining rigs with two or even three power supplies. As long as the video cards are the exact same model and power sources are not mixed, the uptime has been close to 99%.
A cheap power supply is not suitable for video cards. It can be used to power the motherboard and hard drive.
The EVGA 550GA is more than reliable enough with enough power for a single RTX 3080 Ti. Why not make use of that capacity?