PC Upgrade Quick Questions?

AbdullahG

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My current PC is an HP Pavilion Magnesium Gray Edition p6654y. I plan on upgrading the motherboard, CPU, and adding a new video card. The replacements are:

MoBo: http://www.newegg.com/Product/Product.aspx?Item=N82E16813131727

CPU: http://www.newegg.com/Product/Product.aspx?Item=N82E16819115073

Video Card: http://www.newegg.com/Product/Product.aspx?Item=N82E16814130610

My OS cam OEM with the current MoBo. I know I will lose the OS, but can I reinstall it using the same product key, or is it dead? Will my hard drive be wiped clean as well? If so, how do I reinstall the programs I needed that came standard with the computer?