Dell Touch S2240T Monitor bad and dull display problem with HDMI cable

Sir, I purchased your touch Monitor DELL S2240T and I was excited after purchasing it but when I connected it to my laptop HDMI port, I am very much disappointed because the screen display is very dull. White is not really white and bright and black is looks like gray all the time. I tried many settings, for many hours I changed its brightness and contrast but I can't achieve my desired mode. If I compare it to my laptop display the quality looks very bad as if I have purchased very old chinese phone. Please suggest me solution. I am highly disappointed with it.

Mukesh, I own two DELL monitors (though not your S2240T) and overall I am completely satisfied with color production and brightness, infact the Monitor you are using is technically better as its newer. Have you tried connecting it through VGA port or DVI port ? It is also possible that you have an inferior quality HDMI cable. As you said you have already tried various combination then I suggest you try other cable and let me know, do not forgot to try VGA cable also.