Samsung p2450h Not optimum mode on HDMI??

Hi,I have a p2450h monitor which i have had for awhile now and like others would like to be able to watch tv on it. I tried to watch freeview on it from a standard panasonic dvb with a scart to vga lead with no success,(Check Signal Cable RGB message appears),not a problem in its self so i bought a sigmatek dvbr-162 HDMI(not full HD freeview, standard freeview box with HDMI functionality), and you would think ease of connectivity?When connected via HDMI between the monitor and freeview box i recieve the message,"not optimum mode,optimum res 1920-1080 60hertz".I also used a new cable, no joy! My Dad tried the dvb box via HDMI to his 50 inch full 1080p sony, and it worked fine! I also tried connecting a standard dvd-player with a hdmi port directly to the samsung monitor, again via hdmi and sadly with the same result.What could be causing the monitor to not want to accept say a lesser def image via hdmi. I have explored all of what limited functionality the panel menu has exhaustively,no luck! I am a little puzzled as to what could be causing the issue hear,Any info would be great, thnks.