PC audio to Onkyo ht-S5300

[darkphate]

How can i do this without Hdmi when i tried doing hdmi from my pc directly to my computer the screen didnt look right i think its called not syncing properly or something like that. what options do i have? computer specs are as follows....
CPU
AMD Athlon II X4 630 (3.36GHz)

Motherboard
ASRock M3A785GXH/ 128'
Memory
Kingston KVR1333D3N9K2/4G DDR3-1333 4GB (2x2GB)

Graphics Card
Crossfire HD5750s

Hard Drive
WD Caviar Black WD1501FASS 1.5TB 7200 64MB Cache Sound Card
HD onboard

Power Supply
tx 750watt corsair

Case
APEX Vortex 3620 M-ATX


CPU cooling
Arctic Pro 64 GPU cooling
stock

OS
Windows 7 Ultimate 64bit Monitor
32IN HDTV 1080P/50in HDtv 1080i

 

[darkphate]

http/www.newegg.com/Product/Product.aspx?Item=N82E16882120168
home theater^^

http/www.newegg.com/Product/Product.aspx?Item=N82E16814127494R
http/www.newegg.com/Product/Product.aspx?Item=N82E16814150448
video cards