As to the TV hookup, did you undo all that and go back to what worked?
You still could have lost that card. Another card will tell.
I recently bought a new computer. Was very pleased with it (4600AMD,2gb ram) .The graphics card is an Gigabyte Geforce 8600GT 512. Works like a charm with the latest drivers installed.
However yesterday I connected the tv-out converter for the first time and connected the graphics card to my standard PAL tv using an old fashion composite cable. I then turned on my computer and everything 3D including all games had Green Square checkerboard pattern. Re formating doesn't Help and there is maximum air flow.
I Have searched the whole internet and it turns out other people have had this problem but no one has a solution. Can anyone here help me?
Here is a screenshot of Dark Messiah