If you do not have a PCIE slot there is no way to add one. Except for a couple of motherboards that have both slots you will find you either have AGP or PCI Express. Do not confuse PCI slots with PCIe slots they are completely different. If SIW doesn't tell you or you are unsure it will definatly tell you the motherboard maker and model number and if you post that here someone will tell you.
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