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Speaking of sound in the Mac Pro...would buying a PCI(E) sound card work in a mac pro. I am talking about using it just in Windows for 5.1 sound. Something like this.
http://www.newegg.com/Product/Product.aspx?Item=N82E16829102017

Also, if this works would PCI or PCIe be the way to go?

I thought when you install the drivers from the MacOS CD in Windows you get 5.1 through the optical? I am pretty sure that's how mine is right now. Don't need the card?
 
of course the internal speaker is only for system use (beeps ect.) however, it does prove useful run a your final mix's through it. many laptops have low quality speakers such as this one.
 
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