How do get a clean monitor out

In the past I've have been editing with Premiere working with just the computer monitor (premiere workspace) for my viewing. I recently got a new Dell computer with an added black magic intensity card. I hooked an HDMI cable from the output of the card to a LG LCD TV. The quality is terrible with jagged edges and digitized jarble. I tried both SD and HD footage using pretty much ALL of the Black Magic presents in Premiere and nothing. I also tried a seperate 24" dell monitor with HDMI input, and the same results.

On a seperate note, My new computer has 2 DVI output's from the ATI FireGL V7600 video card so I hooked up a second dell monitor using DVI output and switched my playback settings in Premiere to send the program out to the second monitor. Better results, but still jagged edges.

What are people doing to show clients real time HD preview of the project, other than looking at the premiere's workspace program monitor?... which seems to be the only clean image I can actually view.