Yes, a 4K TV will automatically upscale lower resolution content. This is because 4K TVs come with advanced upscaling technology that can enhance lower resolution content like HD or standard definition, making it look stunning on the high resolution display of the TV. The TV does this by adding additional pixels of information into the image to improve its clarity. In some cases, the TV has to do a considerable amount of work to upscale the image. For example, if you're watching a DVD on a 4K TV without scaling, the DVD would fill up only 7% of your screen. However, most 4K TVs use a process called upconverting or upscaling to convert incoming sources to fit their 4K screens, and done right, it can add to the perceived detail of the image.
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