I am not sure about the compatibility of Canopus capture card with DX58SO since Intel has not tested and validated it for this motherboard however if the card can be plugged into the motherboard (which it will), you can install the device drivers that come with your card for your OS and give it a shot. I can not say this with authority but it might just work.
To view the list of compatible parts for DX58SO, follow the URL: http://www.intel.com/support/motherboards/desktop/DX58SO/ and check out the Compatibility.
You might also want to check by updating the BIOS and downloading latest drivers for your card.
Best of luck, thank you and have a nice day!
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