Hi,
Firmware are programs stores in ROM memories in the hardware of the computer's motherboard or expansion cards. I believe that you are looking for the Windows Server 2003 OS Software. For this you can go to a local Hardware provider and to buy from them.
You can check at
http://technet.microsoft.com/en-us/windowsserver/bb512919.aspx for more resources.
Alfredo Arizaleta
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