Here's the thing about HDR. Some TV's may say they are 4K HDR but do not actually have the capabilities to produce good or true HDR.
Find out the model of your TV and go to rtings.com. It will show you how your TV performs in HDR mode.
In order to get the best out of HDR, your TV needs to have a wide color gamut, 10-bit panel, and high peak brightness. Somewhere around 1,000 nits of peak brightness, give or take a little.
If this is not the case, then HDR will most likely look washed out.
As for settings, most TV's when using HDR will automatically default to the proper settings. A lot of them should be grey'd out. It should be on max brightness, max contrast, and you should always be playing in game mode with all post processing settings turned off.
If you have a TV with local dimming, that should be set to high. There might be a setting called something like X-tended dynamic range. Those settings should be on high. Other than than, other post-processing settings should be set to off.
Unfortunately The Show, Madden, NBA 2K don't have HDR sliders to adjust to our TV's settings. They are pretty much set to an average of a good HDR TV.
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