Sorry to hijack this thread, but it could be relevant. As matter of interest, do these cards offer lower throughput than 4x single 1GB cards?
If you should use them in a PCI slot yes, not if you use them in a PCI-X or PCI-e slot (although you could saturate a PCI-e x1 with 4 gbit ports I think).
Not with the Intel Pro 1000's. The PCIe versions require a x4 slot in the dual or quad configuration. Can't speak to the PCI-X version as I don't have any in my inventory.