Introduction
4K Ultra HD is a new frontier for high-end gaming desktops. This resolution pays heavy dividends with visual quality, and on a 28-inch monitor with it, the pixels are so small (with a 150+ dpi pixel pitch) that you practically don't need anti-aliasing. You get to max out texture details (and yes, game developers are dumping some very detailed textures into their games these days).
Image Source: LogicalIncrements
An equally valid high-end gaming PC resolution is 2560 x 1440 at 120 Hz with adaptive-sync technologies, such as G-SYNC or FreeSync. Yet that resolution would need lighter hardware than what it takes to keep framerates above 60 fps at 4K (3840 x 2160 pixels), and we'll cover it in a separate article next week. We recommend setting aside at least $3,500 to build a gaming PC for smooth 4K gaming. Adjusted with inflation, this is the same kind of money you'd spend to build a desktop that gamed at the highest resolution five years ago, or even a decade ago. 5K (5120 x 2880) is a very rare resolution, and would escalate hardware requirements to kingdom come.
For this build, our hardware choices will be utilitarian. We won't pick hardware for extreme overclocking or cheap hardware that falls apart in a year.