It shouldn't matter. Both are pure digital connects and will give the same picture.
in the following paragraph, i will display the graphics card i have.
512MB ATI RADEON X1700SE, 2 DVI
FEATURES: Memory Size: 512MB onboard. I/O Ports: DVI-I, DVI-I/VGA (DVI-VGA adapter included), TV-Out (S-video/Composite adapter). BENEFITS: A multimedia powerhouse, this graphics card delivers outstanding visual realism, stability, and performance. Whether it's gaming, movies, digital photography, or video playback, the ATI X1700SE offers Vibrant colors, ultra-sharp images, and lifelike image reproduction, for an optimal entertainment experience. Innovative graphics architecture and HDCP capability to allow digital playback of protected content. It is optimally designed for a consistent HD-DVD experience. HD-DVD playback requires applicable HD-DVD Play player. As HD DVD is a new format containing new technologies, certain disc, digital connection, compatibility and/or performance issues may arise, and do not constitute defects in the product.
my question is: inorder for me to get the BEST possible picture using a plasma display, would i use the dvi-i output, and convert it to hdmi, then put it in my display as the hdmi plug? or would i just go from dvi-i to dvi-i on my display? help on the best picture please!!!!!

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