To determine if Mac OS detects your expansion card, you need to check System Information to see if the card is listed under the appropriate heading or is listed with an error (for example, Device has not been configured). An example of an appropriate heading for a network card is Ethernet Cards. The expansion card is listed in System Information as the name of the chipset. You can find the name of the chipset on the Technical Specifications tab for the product ID on www.startech.com/Support.
To open System Information, complete the following:
If you installed a new PCI or PCI Express expansion card and Mac OS cannot detect the card, you can complete the following troubleshooting tasks to help to resolve the issue:
Note: PCI Express cards work in PCI Express slots that are longer than the card and do not use the entire slot's capabilities. PCI Express expansion cards do not fit or work in PCI expansion slots, and PCI expansion cards do not fit or work in PCI Express expansion slots.
If you completed the previous steps and determined that the problem is not with the card or expansion slots on the motherboard, you may need to update the EFI firmware on your system.