dell xps: can 4K video cards (9.4 megapixels per frame) can support 5K at medium height (7.3 MP)?

I'm really interested in the new Dell Ultrasharp 49 "32: 9 screen (5120 x 1440 ~ = 7.3 MP), but most laptops only support 4096×2304 at 60Hz (9.4 MP) …

Since this 32: 9 aspect ratio screen is delivering fewer real pixels, is it curious that the video cards are actually limited by the total of pixels, or if they are limited by the horizontal and vertical resolution?

Specifically, I am using the XPS 13 9350 that has an Intel Core i7-6560U / Intel Iris Graphics 540 with DP support for 4096×2304 at 60Hz.

Would there be a specific Linux problem running this?