ATI has resolved the Yamaha non-compatible Issues

I have successfully connected my ATI-78oG-based HTPC to my Yamaha RX-V663 and Sony LCD TV. That means I could use the full video features of my Sony under the TV/Video modes for my HD contents now. Previously I connected my HTPC directly to my Sony under the PC mode as the Yamaha could not talk to my ATI-based HTPC, and thus end up I could only get it worked under the Sony's PC mode by direct connection with a HDMI or D-sub. The disadvantages were that Sony do not allow you to use most of the video features under the PC mode, you are only allowed to switch between Text Mode and Video Mode (minimum video features) under the PC mode.

You need the latest Catalyst driver from ATI (or AMD) to enable your ATI-based PC to talk to the Yamaha. I used the "9-5_vista32_win7_32_dd_ccc_wdm_enu" vesion and it works perfectly for me. Remember, it is the ATI driver issues, not the Yamaha. I didn't update any firmware to my Yamaha. Now, I summarize my findings and results below for those who are interested:-

1. No firmware update is needed for the Yamaha.

2. You need the latest Catalyst driver (e.g. as at 14 June 2009).

3. Yor need two HDMI cables, one from your HTPC to the receiver and another one from the receiver to your LCD TV.

4. No optical cable is needed.

5. Your LCD TV will treat the source from your receiver as ordinary HDMI source (e.g. DVD players etc.), so do not try to read texts under this setting, it's too bright for your eyes (similar to viewing texts under the 'Movie Mode' under a typical LCD monitor). The TV should give you a resolution of 1366x768 now (with some fine tuning), no more 1360x768!

6. If you do want to use your LCD TV as a monitor occasionary, then use a D-sub to connect your HTPC to your TV (provided your TV has got one D-sub input, if not, use another HDMI input. But your HTPC may not have 2 HDMI outputs, and you already use one for the receiver). If you set the resolution at 1360 x 768 (for non-HD LCD TV), you should be able to work uner the PC mode. You can shift to this Text mode with your TV remote. Under the PC mode, you still do not need an optical cable for the audio. What you need is switch on the receiver for the audio (your TV speakers won't work under the D-sub, but your 5.1 speakers which connected to the receiver will work).

That's all.