For my LCD, HDMI to PC's DVI gives the cleanest output.
If I use VGA cables, there is this ghosting signal noise crisscrossing the screen that's very annoying. It's the same whether it's a 1.8m or 8m VGA cable that I use.
My PCs' vid cards are Inno3d 8400GS, ATI 9250 and Inno5500. Any of these three PC's that i use, as long as it's the DVI output, the panel gives the best image.