I want LPCM 7.1 uncompressed >20Mbit/channel (HD-Audio) out not AC3 5.1 (compressed 1.5Mbit/channel). Dongle just convert DVI to HDMI it has noting to do with HD-Audio.
Also, ATI HD 2600 DO NOT support HD-AUDIO. It only support AC3 5.1 (same thing as Coax can do).