A PC to drive the 3840x2160 today has dual to a trio of GPUs to get 30 FPS during gaming. Even playing a movie would be a high end rig. I would not rush to UHD on a PC today.
Not only are you looking at more for the display but a few thousand in GPUs.
I have always preffrred pixel quality over resolution and wanted an OLED display for some time now and while they are presently to expensive I was wondering when it is likely that a normal sized (27-40") monitor would even be for sale. I have no intention of buying an OLED television ever and love my present monitor but I assume that when one comes out it will be 4k and I don't mind spending the money on what I think is a needlessly high resolution if it is capable of absolute blacks.

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