OK, the 50 inch TV at 4K you may have to sit from 3 to 6 feet from eyeball to screen to spot 4K differences.
Then again we have a 4K series of articles from CNET such as https://www.google.com/#q=CNET+4k+is+stupid
To game at 4K looks very expensive. Read http://www.cnet.com/news/hands-on-with-nvidias-new-titan-x-graphics-cards/
Bob

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