Story time
So I had this setup right, 6x RTX 3090, custom frame, mas the thing was tipo a space heater with attitude. 2 years of this, 3 PSU deaths, 1 almost actual fire. Não recomendo.
Sold the whole thing for, bought used Tesla V100 from Vultr. Single 2U box. Boring? Sim. Reliable? Also sim.
The numbers
Rig: 847 days uptime across all cards (combined), 11 RMAs, 2 house breaker trips
Server: 641 days so far, 0 hardware issues, 1 planned maintenance
Render time on my workload (blender, cycles): actually 15% slower per card. Mas I dont care. I sleep now.
Someone will say consumer cards are faster per dollar. Tipo, sure, if your time is worth nothing and you enjoy replacing thermal paste at 2am.