You would need to locate or build a custom PCI connector, then wire it to duplicate every connection to a computer. Software would need to do the same as a computer does, communicating with your PCI card.
You may as well use a computer to test your card. Only a certain range of years and models contains a PCI connector. And your card is likely to be compatible with either Mac or PC, but not both. It may require a particular series of OS as well.
Did the card come with a CD containing driver software? Or else the software can be downloaded from the manufacturer's website, or from a 'sharing' website.
A lot of things need to be just right, for the card to work successfully. I put a wireless networking PCI card in my aging G5 PowerMac. I had to go through a lot of antics before I got it to work properly. I had to play with settings in the Preferences, I had to power down and start up, etc. This was several times.