Sony 50" A3000 SXRD here. No problem initially with old 6600GT and older drivers DVI-HDMI + analog RCA.
I wanted the benefits of 8500GT for recordings from my new HD PVR. However, the card would never sync with my TV via DVI-HDMI. My whole system would stall after post with the card connected, would not even make it to the splash screen. I had to unplug it, wait during boot, and "hotplug" - not an option! Opened a big long ticket with nVidia : no resolution. I did not want to settle for component video. My analog audio stopped working after updating past the 169.xx driver. I finally tried the spdif cable to my sound card (a 10+ year old SB Live value) which does not even have an SPDIF out. Luckily, I found a pin out of the 20 pin connector for a daughter card, and there was an SPDIF out buried in it. So this worked IF I hot plugged. Frustrated, I almost went to the dark side with ATI, but thought I would give it one more go.
I then purchased a 9500GT with native HDMI, and it synced to the TV perfectly, not even overscan during post. It did not matter HDMI-HDMI or DVI-HDMI, it looked great! The only problem, I had no sound after installing the Geforce drivers, even with the internal SPDIF connected to my sound card. I disconnected, and tried the old analog method - nothing either. As soon as I uninstall the driver, sound is back. Another ticket opened, and after being escalated to level 2 on 01/01/09, no response. My HD PVR is useless if there is no sound to go along with the incredible picture.
I am running Windows XP Pro SP3. ASUS 9500GT OC 512MB DDR3.
I saw a DLP fix somewhere on here, but looked like it was only for vista...hope someone fixes this soon without some kind of EDID hack. I have just about had it.