HDMI surround sound

my computer is connected to my surround sound box then to the TV. But windows only lets you choose 2 ch stero output via the HDMI. The only explaination i could come up for this is that windows detects my TV having only two speakers and doesn't detect my surround sound having 7.1 speaker set up....? how can you force win 7 to output 7.1 via HDMI????

Windows is not "detecting" your TV - it doesn't know or care what is connected. However, many systems only output two channel stereo via the HDMI and it's up to the TV or surround audio system to provide the surround sound. This is also true of the S/PDIF output on many systems.

If windows does not know what is connected then why does it have the information of my tv monitor including the max res, refresh rate and the model????
I know for a fact that the video files that i play have 6ch's to output but windows will not pass them on as it only lets you choose 2ch for HDMI. So maybe my theory is wrong but there should be no reason why windows shounld not be able to output dolby 5.1. The anoying part is that windows will let me set the normal speaker outputs on the back of the computer to dolby 5.1 surround sound.... surely there are ppl out there who can get surround sound through their hdmi set up...

You didn't list your hardware profile in the System Specs. Knowing what you have will help someone to help you with the problem.

AMD Athlon 64x2 5200
MSI main board K9AGM2
32" LCD 1080i