42in plasma samsung

[Misterfast3]

wasnt sure if this is the right place. but you guys seem to maybe know. i use my 42 in plasma with my computer to play games. a dvi to hdmi. hdm1 doesnt have 3d. but the clearity of this picture is horrible no matter what resolution i goto. but on hdmi 2 if i turn 3d mode off, the picture looks absolutely awesome! my problem... approximatley every 30 minutes my tv goes from 3d mode : Off to 3d mode : mode 1. in mode 1 the picture quality goes very bad again. it just started doing this about 2 days ago. can anyone please help!? thank you...