NVLink vs. SLI and Multiple GPUs - Is it worth it?
Early Blender benchmarks suggest that two NVIDIA GeForce RTX 3080 cards would outperform a single GeForce RTX 3090 had NVIDIA included NVLink support - NotebookCheck.net News
ASUS ROG GeForce RTX NVLink Bridge with Aura Sync RGB, 4 Slot - Newegg.com
Quad NVIDIA GeForce RTX 3090 Graphics Cards Tested, Insane Content Creation Performance at a Brutal 1700W