I was doing a bit more searching....... AND
You're going to need a 4 pin to 6pin adapter... seems Corsair skimped on them...
I've just maybe changed my mind
sorry, 4 pounds more but modular, better for the 900, and has more connectors including 2 pci-e cables.
Antec Basiq Plus 550W Modular Power Supply  Power Supplies Antec
Or, maybe this coolmaster, though i don't know much on them, but a 5 year warrenty.
Cooler Master GX 550W Power Supply [RS-550-ACAA-E3] Power Supplies
But the Corsair will work too, just need the adaptor and daisy chain your fans....
For the record i was alittle sleepy when i posted the first one and forgot about the 900 and its fans.