How do i connect a 2nd PSU?

I have a 1000W PSU now running a 3060 and a 3080, i want to add 2 more 3080 but i dont think the 1000W are enough. How do i connect another PSU the safe and fire proof way?

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Reaching short over 50MH/s with 3080 with -200 core +2300 mem and 289 Watt PL. On Ubunto Linux btw with T-Rex miner.