Initial benchmarks suggest that the GeForce RTX 3090 should outperform the RTX 3080 by up to 23.5% in professional applications, according to a new report. That is a far cry from the paltry 5% improvement in some gaming benchmarks, but two RTX 3080 cards would beat an RTX 3090 in professional applications if NVIDIA had enabled NVLink.
https://www.notebookcheck.net/Early-Blender-benchmarks-suggest-that-two-NVIDIA-GeForce-RTX-3080-cards-would-outperform-a-single-GeForce-RTX-3090-had-NVIDIA-included-NVLink-support.494789.0.html