OCC has published a review on the XFX XPS-650W Power Supply
A quote from the article:
>> XFX XPS-650W Power Supply Review
The XFX XXX Edition 650W power supply is certainly worthy of consideration for use in any high gaming system and will easily handle any single high-end graphics card gaming rig with plenty of room to overclock. There are a total of four PCI-E connectors available on this power supply so crossfire or SLI is definitely an option but keep an eye on power requirements especially with the more power hungry Nvidia offerings.
>> XFX XPS-650W Power Supply Review