M1530 VGA-to-RCA Problems

Hi. I recently bought a VGA-to-composite adapter for my Dell M1530 laptop so I could connect it to an old RCA-made tube TV that I just bought at a steal from a friend. All I was looking to do was have an HTPC so I could watch some DVDs, maybe play a little (crackly, low-quality) music.

I plugged in the RCA adapter and all the composite cables to both the TV and laptop, but there was no result, even when I pressed Fn+F8 (Dell's "CRT/LCD" switch). I went into the nVidia Control Panel (the machine runs on an 8600M) and set it up for multiple displays using Dualview, even making the primary monitor the old TV. I set the resolution of the TV-Out to 640x480 (the closest a computer can come to NTSC, I think) and the refresh rate to 60Hz.

Still, the only effect it had was to produce a little crackly noise and a slight flicker on the TV, but it went right back to a black screen.

Any ideas?