Hi everyone,
I'm not sure if this the right forum to post this problem. Anyways, I am using my new LCD 42" Sharp Aquos (model LC-42D43U) TV as a monitor. I tired first using DVI to HDMI cable from video card to TV and the picture had some pixelation and artifacts on screen i.e when I play any movies through Media Player. Then I tired using the s-video to component converter which came with the ATI 2600HD Pro video card and this is where I'm having the problem. When Windows loads up the screen goes green and the desktop appears for a few seconds and then the video goes competely black. The screen did indeed look a lot nicer. For some reason I can see in the top right hand side of the screen that the setting changes from 480p to 720p before it goes black. I have the latest ATI drivers installed and the card was purchased less than a month ago. I also called Sharp TV for help and they were totally useless. They said that the problem lies within the video card since all the other inputs (HDMI, VGA, S video work all fine). I also tested my DVD on the same component output and it works fine. The other problem I am having now is that I can't even change the settings in Windows in order to troubleshoot the card further. I suspect it could be the s video to component adaptor but I'm not really sure. I am using good quality cables as well (RGB). If anybody can please offer some advice as how to I can get back into Windows before the screen goes black, I would appreciate very much.
Thanks.

S-video can't carry 720p-even when you are then converting it to component-so this may be part of the problem (you are essentially telling the card to put out a non-standard resolution).

Try rebooting the computer with a VGA cable between it and the display or a computer monitor, and perhaps you will be able to change the resolution back to something you can see onscreen with the Aquos.