Razor has a 17” laptop that can be configured to have a 4K display, but you also have to upgrade the GPU to a RTX 2080 Max-Q. The RAM and storage is end user replaceable though and you’d have an absolute beast of a machine that could handle pretty much anything you’ll ever throw at it. It is $3700 though. https://www.razer.com/gaming-laptops/razer-blade-pro/shop