Hi,
as far as I know 8800GTX does not support secure way to pass-through so HD audio is not allowed by AACS rule
Please also check:
http://www.cyberlink.com/products/powerdvd/spec_en_GB.html
HD Audio Compatible Sound Card and Codec List
•Realtek ALC679X (support up to 192kHz/24bit 2-6 channels)
•Realtek ALC898 (support up to 192kHz/24bit 2-8 channels)
•Realtek ALC899 (support up to 192kHz/24bit 2-8 channels)
•Realtek ALC672 (support up to 192kHz/24bit 2-6 channels)
•Realtek ALC885 (support up to 192kHz/24bit 2-channels or 96kHz/24bit 4-8 channels)
•Realtek ALC889 (support up to 192kHz/24bit 2-channels or 96kHz/24bit 4-8 channels)
•Realtek ALC669 (support up to 192kHz/24bit 6 channels)
•Realtek ALC670 (support up to 192kHz/24bit 6 channels)
•Realtek ALC892 (support up to 192kHz/24bit 8 channels)
•VIA EnvyHD Vinyl VT1818S codec (support up to 192kHz/24bit 8-channels)
•VIA EnvyHD Vinyl VT1828S codec (support up to 192kHz/24bit 8-channels)
•VIA EnvyHD Vinyl VT2020 codec (support up to 192kHz/24bit 8-channels)
•Auzentech X-Fi HomeTheater HD (supports HDMI 1.3a bit-stream lossless pass-through)
•AMD Radeon HD 5000 and 6000 Series graphics cards supporting lossless pass-through
•NVIDIA GeForce GTX 400 Series graphics cards supporting lossless pass-through
•Intel Core i3/i5/i7 with integrated audio and graphics
Technical Support
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