edit -
IDK if this helps but you can try game mode, there's a manual to your tv on their support page - http://www.samsung.com/uk/support/model/UE46F5000AKXXU
Game Mode is a setting used to bypass different operations in the TV. When Game Mode is enabled one of the major changes is the DNIe chip in the TV is bypassed. Bypassing the DNIe chip disables some video processing in the TV, which in turn allows for a faster video response time. This is useful when viewing a fast-paced video source such as a video game.
With your TV powered on press the MENU button to open the Main Menu.
- Use the navigation pad to select the System menu and then press ENTER.

- Use the navigation pad to select the General section of the System menu and then press ENTER.

- Use the navigation pad to select ON for the Game Mode option and then press ENTER.

- Press the BACK/EXIT button to leave the menu.
NOTE
● Precautions and limitations for game mode
– To disconnect the game console and connect another external device, set Game Mode to Off in the setup menu.
– If you display the TV menu in Game Mode, the screen shakes slightly.
● Game Mode is not available in TV mode.
● After connecting the game console, set Game Mode to On.
Unfortunately, you may notice reduced picture quality.
● If Game Mode is On:
– Picture Mode is set to Standard and Sound Mode is set to Movie.
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on the topic of 4k sets
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If I was considering getting a new 4k set for less then I would look into the Vizio P series.
It's an entry level 4k set that starts at $999 for the 50" and has some good reviews so far.
I would check out any set in person, and if you live in the US then wait for Black Friday deals.
http://www.theverge.com/2014/9/23/6832447/vizio-p-series-4k-tv-release-date-pricing <-- general preview
http://www.rtings.com/reviews/tv/lcd-led/vizio/p-series <-- in depth review
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edit- if you don't live in the US the Vizio P set might not be available to you
and if you're looking for a tv that is 1080p and mostly used for gaming then the above Sony sets are better
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