Try the 10.10 Drivers. (Or the 10.10E's if you can find them) Those were *really* good drivers and still are todate unless your playing BF3 on your PC.
Those should be old enough. Since you don't remember. Other good drivers from the 10 series would be the 10.5's as well IIRC. See if you have any luck with those.
If you need even older you can look up the 9 series drivers as those were released with the 4k series when they hit market.
Need to get the TV to show up in CCC before I can say anything else. Because I know you can play around with pixel formats like 4:2:2 / 4 4 4 ect... to see if your TV would get a picture. But if the TV's not even showing up then you can't adjust anything.
I moved my old 4870 out... about 6 months ago and I'm useing a 5770 for my HTPC so I can't try to recreate the whole "not detected" error your getting. apologies. Seems wierd that the 12.1's just won't work with your TV...
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