I have a PCI-GPIB card and the computer has PCIe slots, so I need to know if this card has compatibility with PCI express x16. Or I need to order a PCIe GPIB card, the computer has PCI express x1 too.
Unfortunately, PCI-express and PCI are not cross-compatible.
This means you can install the PCI-GPIB card only in a PCI slot.
If your computer has only PCI-express slots, then you would need to get a PCIe-GPIB card. Alternatively, get a computer with PCI slot if you want to use the PCI-GPIB card.