According to a Valve Engineer, the Steam Machine specs outclass the most common PC configurations. The company relied on its own hardware surveys to choose the system’s components. Even as an entry-level option, Valve claims that 4K/60 fps performance is realistic, despite a memory-limited GPU.
That’s the thing, 1080p monitors are very common…maybe the most common. If that’s your resolution, a 1080ti will take care of you just fine. If I can keep my 1080ti’s fans from dying, I will probably use that card for another 5 years.
Do you clean your case filters? It’s something I don’t do enough of but it would probably help.