Let's be honest here, a similarly speced PC offers very little over this iMac. Finding a 5K display that good takes up a large amount of your budget right off the bat.
These new 5K iMacs are the best value computers Apple has made in recent memory. Dedicated graphics cards, upgradable CPUs, Upgradable RAM, a Full I/O compliment including USB 3.0 and Thunderbolt 3, and finally that absolutely stunning 5K display.
The Radeon Pro 580 (RX 580) is a great graphics chip and can game very well at 1440p.
Building a similar PC is possible, but it's still nowhere near as elegant.
