The power is a good question. The QuickSilver card has a data and a power cable. The power cable connected to the old style IDE power connector. It looks the newer cards have the place for the data and power cable. I know for the external PCI card, I am thinking the data for the newer cards would plug into the logic board from on the two empty connectors marked ODD_SATA. The other two empty connectors to their right is were my video card power plugs in.

I am not sure what is behind the connectors for the sled.

Another card:

http://eshop.macsales.com/item/NewerTech/MXPCIE6G2S2O/