It is essential, however, for hardware gurus to note that using only two 8-pin connectors will not supply enough power, which will prevent the system from starting up properly. Testing conducted ...

TL;DR: NVIDIA's RTX 5090 graphics card requires 4 x 8-pin connectors for 600W power officially, but can operate with 3 x 8-pin connectors at 450W, seemingly running only 5% slower in 4K benchmarks.