a 5670 may work, depending on the exact PSU (please state brand and model and any specs written on the PSU). not all 220w psu's are created equal. Even then i would say using that card would be pushing it. A GT220 would be more realistic and should be ok on that PSU. It will not be as fast as your old 8800 though. Basically, anything that requires an extra pci-e power connector will not likely run on that PSU.