The NVIDIA GeForce RTX 4090D is the objective winner of this comparison, securing victory in eight out of thirteen categories. Its most significant technical advantage is its shader unit count, which is 470% higher than that of the Intel Arc B580. While the Intel Arc B580 holds its own in four specific areas, the substantial lead in core processing architecture makes the NVIDIA GeForce RTX 4090D the superior choice for raw hardware capability.

Users prioritizing maximum computational power should select the NVIDIA GeForce RTX 4090D to leverage its massive shader unit advantage. Conversely, the Intel Arc B580 is the better option for budget-conscious buyers, as it offers an 84% better MSRP compared to the alternative. Choosing between these two components depends entirely on whether your primary requirement is the highest possible hardware specification or the most favorable initial purchase cost.