TV Out on radeon 7500

[nikosapi]

Hello,

I just got an old pci radeon 7500 card for its TV output capabilities (I'm 
using two of the outputs on my nvidia card already).

I've upgraded to Ubuntu Gutsy and I've also gotten the latest radeon drivers 
and xrandr from git. I got information on how to do this from: 
http://mailman.linux-thinkpad.org/pipermail/linux-thinkpad/2007-August/039878.html

Using xrandr I am able to issue the following commands which makes the blue 
screen on my tv very jittery (I assume it's because the card is feeding the 
TV a bad signal):

xrandr --addmode S-video 800x600
xrandr --output S-video --mode 800x600

Then if I try to set the output to ntsc (xrandr --output S-video --set 
tv_standard ntsc) I get the following error: 

X Error of failed request:  BadValue (integer parameter out of range for 
operation)
  Major opcode of failed request:  159 (RANDR)
  Minor opcode of failed request:  13 ()
  Value in failed request:  0x1b9
  Serial number of failed request:  20
  Current serial number in output stream:  21

Although if I do: xrandr --output S-video --set tv_standard pal I get no error 
message. Does this mean that it doesn't support ntsc? The only 
other 'tv_standard' that I found that doesn't give me an error is 'default' 
which produces an even more violent jitter on the screen.

Here are some files that might help figure out the problem:

Xorg.0.log: http://nikosapi.org/other-stuff/Xorg.0.log.txt
xrandr --verbose (with CRT snd TV attached): http://pastebin.ca/735489
xorg.conf: http://pastebin.ca/735500

Please help,

nick