TVs this cheap will push more 4K TVs into the mainstream, which will in turn nudge holdout content providers into offering it. While Vizio's D-Series offers middling panel tech and no Dolby Vision HDR, Android TV or other perks, current owners of basic HD sets will see a big difference in quality. Budget-conscious buyers will also get support for Ultra HD game consoles like Sony's PlayStation Pro, Ultra HD Blu-ray players and 4K cable or set-top boxes from the likes of Google Fiber and Roku.

Vizio, which was recently bought by troubled LeEco, pushed out some interesting higher-end 4K options last month too, including a 75-inch 4K E-series model with basic HDR for just $2,000. If you really want 4K Dolby Vision HDR without spending too much, you'll need to go for Vizio's P-series, with 55-inch sets at $1,000, or switch to TCL, which offers a 50-inch 4K Dolby Vision TV for just $500. For the sake of comparison, Sony's 55-inch 4K OLED TV costs $5,000, showing the wide gulf between the low- and high-end.

Vizio's 4K sets are now available at Walmart, Target, Best Buy and other retailers. 4K models run $420 for a 43-inch set, $500 for the 50-inch model, $570 for the 55-inch version and $900 for the top-end 65-inch model.